I assume you're familiar with this site, but it's where I'm basing my project off:
http://reefprojects.com/wiki/Main_Page
Parasite mode allows you to control several of the DS18B20 temperature probes using a single wire to the arduino (very valuable when there are so few ports!). I haven't gotten it to display the two probes I have connected separately yet, but that's really a matter of taking the time to learn the code used in the examples.
For my probes, you need a 4.7k resistor on the +5v lead, so I wired it all up and heat shrunk it. I then put it in a tube you can get at the pet store. It's like rigid air line tubing only slightly larger, then epoxied the ends closed.
I have all my relays now, but I'm still waiting on the RTC to arrive and the serial connector for the LCD.
How do you intend to control your other component with the LCD shield on the arduino? Can you control the relays and LCD on the same I/O ports? I have seen port doublers for sale, but I have no idea how the coding works or circuitry.
Here's a picture of my LCD running. I'm planning on building a black acrylic box to put the LCD and keypad in. I haven't picked the keypad out yet but I'm not sure what my options are for interfacing with the arduino.
