[ladyada] has a freshly-published and amazingly thorough tutorial on passive infrared (PIR) motion sensors. Most often seen in security floodlights and automatic doors, in creative hands these sensors ...

I'm trying to decide between two 3D TVs: a Panasonic that's active 3D and LG that's passive 3D. LG has all these international certificates for the best 3D picture and claims it's full resolution, but ...