WS2801 LEDs as bed light

I'm planning to mount a bunch of WS2801 under my bed, hook them up to an Adruino Uno and combine them with a motion sensor to lighten my bed. I still have some LEDs left over from a different project. I've been looking at what I need and so far I gathered these things, summing up to 46€:

HC-SR501 motion sensor - 8€
[Adruino Uno Rev 3]( - 24€
Nice case - 10€
Power connector for the LEDs - 5€

I'm still missing a power supply for the LEDs, but I'll check tomorrow which one I'm using for the other LEDs and I'll add them then. I do have enough cables etc.

**My Questions:**Would you guys agree with the things I'm planning to buy? Would you do it differently? Can I save some money anywhere? I just want some kind of confirmation before I order everything.

I basically want something easy to use. Since I like to build these kind of things on my own, I decided to do it this way. I found this on Amazon as well, it might seem a little easier (just look at the pictures and you'll get the principle). What I miss at this alternative is the lack of settings. I can't change the light color, the sensor is only okay according to reviews, and I have much more LEDs than I need, because I'll only light the one side of my bed (2m).
Thanks in advance!