Please post you complete code and not just snippets. Also, please use the code tags

Code:

code tag

This will very much improve the codes readability on the forum.

Most high power LEDs are first reflow soldered to a mcpcb ( metal core printed circuit board ). That mcpcb while itself being a form of a heat sink, is usually too small to dissipate the heat of a 700mA LED. Thus, that mcpcb with the LED then is mounted to a bigger heat sink either with thermal epoxy, thermal tape or thermal paste and screws.

Reflow soldering this LED " in the raw" to an mcpcb takes some form of equipment that most beginners don't have on hand, or experience with.

If you are interested in that specific LED, perhaps look for a supplier that has this mounted already on a mcpcb.

Here for example:
http://www.ledsupply.com/creexml.php

@ oric_dan

Thanks for that bit of information. Thsi has never crossed my mind and may actually explain a problem I had in one of my projects!

This is a very interesting articel of the effects of these pull-up resistors on the I2C signal.
http://dsscircuits.com/articles/effects-of-varying-i2c-pull-up-resistors.html

Aside from the impossibility of displaying the EXACT color as another device/ screen, how would you specify " not too expensive" and particularly " Arduino compatible" ?

Judging by your code I guess your are trying to fade all LEDs in the LED strip at once ?

A very efficient method to change all three colors at the same time ( well...mor or less) is to implement a 3D bresenham algorithm. Think of it as drawing a line trough a rasterized 3D space with the three coordinates not being x, y and z but red, green and blue.

With that being your base algorithm, you can simply fade between any given color mix. You define two points and the algorithm draws the line resulting in smooth fading between the two ( color)points.

If that's what you a looking for, I've implemented it in my LED lighting systems trippylighting.com and I'd be glad to share. It's still quite work in progress but works nicely as is already.

The reason your sketch generates such a large binary is simply that the protocols you are using are quite "fat. If you just want to read a stream of sensor data then raw UDP is a much better and faster way to do it.

Perhaps a more detailed explanation would provide more guidance of help. I agree that "secure" as in encrypted is rather out of the question on say an Uno or a Leonaro.

Tere have been several Arduino compatible 32 bit ARM Cortex boards released lately that may be able to do that. The Teensy 3 might be a candidate or the Galago.

No, WiFi is not hard to do. If you use a little router connected to the Ethernet shield, for example a TP-Link TN Wr702n it is very simple. This is a little travel router that comes configured as an AP ( Access Point, or Hotspot). You can integrate it also into an existing network if you so desire.

You should be able to use any WiFi enabled phone to connect to it. I can verify that it works with an iPhone and iPad.

Once connected, or should be able to run any of the sample scripts that come with the Ethernet library and they should run without problems. The WiFi connection is transparent to the Ethernet shield.

Very nicely executed! From the clean and well organized layout and installation in the electrical enclosure to the beautifully crafted web interface.

Finally I have some time to post my own project.

From an Arduino standpoint it may not be overwhelmingly complicated but it was quite an effort to bring it to this relatively finished look and function.

The attached image shows how it is installed in my house and of course is rather static ( the image that is). I started documenting it on a little blog trippylighting.com that has a little YouTube video embedded and will have some more info on it soon.

Hardware:
The controller is not an Arduino but a Teensy++ 2 as I needed more flash memory due to the libraries I am using. The LEDs are 700mA Luxeonstar rebel RGB LEDs. Each RGB led is connected to a Hi Power RGB Led shield. http://neuroelec.com/hp-rgb-led-shield/ver-2-0-manual/. While these are shields that you can stack on top of an Arduino they only communicate through I2C with it and due to the very different form factor of the Teensy++ I have used Cat5 cable to connect all the LED driver shields to the Teensy.
Connected to the Teensy++ is a WIZ812 Ethernet module which in turn connects by means of a little Ethernet cable to a little TP-Link WR703n WiFi router to be able to remotely control the functions from an iPhone

Software
I started this with the "normal" Arduino IDE but have merged over the code to use with the Arduino Eclipse Plugin and Eclipse. This is a beta version of the plugin that will support The Teensy boards when released.
I am using the DHCP/Bonjour libraries to connect an iPhone and iPad to the lighting system in true ZeroConf fashion. The ArdOSC library provides OSC protocol function and in conjunction with the TouchOSC I can remotely control the lighting system.

The color changing sequence is in essence a 3D Bresenham algorithm. I randomly draw a line through that color space.

That's it for now. I will provide more details soon on my little blog trippylighting.com

Senior designing what ?

I'd suggest you start using the search function of this forum. During the last 3 months or so I have posted a good handful of times in respect to Arduino and WiFi. Usually I suggest to use a little wireless router in conjunction with an Arduino Ethernet shield ( not a WiFi shield).

I believe for beginners that is easier to deal with than any of the WiFi solution that are presently available. You have the full functionality of the Ethernet library at your hands and that library is mature enough so it's save to assume that potential bugs are in your co and not in the library.

If you have to go the WiFi route - and I question that this  is always necessary - and size matters to may want to look at the Platinum @ diysandbox.com. It integrates an Arduino compatible processor and a Gainspan WiFi module into a unit much smaller than any Arduino+Shield configuration.

Before attempting a solution with a WiFi router I tried my luck with a WiShield or the CopperHead - a clone of the WiShield. Ascynlabs, the maker of the WiShield closed their doors so ther is little if any development on the software side and there is not much traffic on the forum. I got it to receive raw UDP, but that was it. I could not integrate the ArdOSC and DHCP/Bonjour libraries to work.

While physical size is not so much of a concern in my projects trippylighting.com, due to the ( compiled) code size I wanted something with more flash memory than the UNO and found the fully Arduino compatible Teensy and Teensy++ controllers. The Teensy++ has 128k of flash which solved that problem. These boards are a magnitude smaller than an Arduino UNO not to speak about an Arduino Mega. You can combine a Teensy http://www.pjrc.com/teensy/ with a WizNet Ethernet module that works equivalent to an Ethernet shield http://www.saelig.com/BRD/ETH042.htm, or if that still is not small enough you can use this one http://www.saelig.com/BRD/BRD032.htm

All of the above is much, much smaller that an Arduino Mega with a WiFi shield. I have the Teensy++ connected with an Adapter board to the WIZ812 module in two projects, connected to a TP-Link WR703n in one case and a TP-Link WR702n in the other case. Works flawlessly in both cases.

The TP-Link routers are each around $30 and their footprint is half the site of an iPhone4 and about 2.5 times as thick.

The other approach for your project is to have only one WiFi shield on a central Arduino that communicates to the Internet and use another wireless technology - Xbee for example - to communicate to the units that are installed in the electrical outlets.

If you already have an Ethernet shield that you could continue to use for this project, then buying a rather expensive WiFi shield is unnecessary.
You don't need a WiFi shield to do WiFi with an Arduino board. You can simply buy a little pocket router for $30, for example a TP-Link wr702n and connect it with the short Ethernet cable that comes with it to the Ethernet card and you're in business.

I've done this in two projects already and it works like a charm!

Yes, you will have an Internet connection, but then it  depends what you want to send or receive through the connection and if the connection will be initiated from the Arduino to the out to the internet, for example to post the data to a web site ( relatively easy) or if you want a web site to initiate a connection from the outside to your router (somewhat less easy).

I agree that in certain use cases the Ethernet card is a bit superflous, but if you start that argument you may as well replace the whole Arduino, again depending on what you do and what your embedded coding skills are.

The TL WR703n hosts a 300Mhz Atheros processor (Arduino 16Mhz) with 32MB dram (Arduino MEGA 128kb). It has some GPIO and OpenWRT is an embedded Linux box.