The stuff from wirelesstags.net are generally very good. I have a bunch of sensors and their Reed sensors for detecting opening and closing of doors are very good. I hook it up with ifttt and turn on my Hue lights when I open and close my doors. Clearly not ground breaking stuff but useful.
The Hue lights are great but expensive. The Hue switch made things a lot more useful as well. I'm waiting for them to come out with a compatible light switch so I can control my recessed lights the same way as my light bulbs.
What they need to work on is a better outdoor camera with motion detection that doesn't get triggered by shadows or wind moving a tree branch. I've tried almost every solution and none is acceptable.