I don’t have a lot of time these days to play around with little sensor/micro-controller projects these day, but thought I would start putting together a reference for when I do have the time.  One of the projects I did was a curtain controller which closes and opens a curtain on command through a USB cable connected to a spare laptop.  I didn’t use a wireless module because at the time I couldn’t find a solution that was cheap enough, but I just saw a few options at Sparkfun that might work.  Other possibilities might be to incorporate a few photo(ambient light) sensors and a temperature sensor to provide additional inputs so the curtain can open and close itself, in addition to being able to operate by SSH’ing in to the laptop from a remote location.

Micro-controllers:

• Arduino‘s website calls itself “an open-source electronics prototyping platform based on flexible, easy-to-use hardware and software.”
• Crossbow seems to have gone a bit more proprietary since the last time I looked (in 2006).

Fairly affordable components available at:

• Sparkfun

Other resources for circuits ready to build:

• ElectronicsZone
• Free-Circuits.com