i bought this Veho vcc-003-muvi-pro 30fps, comes with a 4gig micro sd good for about 160 minutes of video WITH timestamp! it gets the job done for $50.
the nice thing it you can have the power "on" and it will hibernate and if you need to start recording you simply hit the top button and yer good. to stop hit it again. you can repeat this till the card is full. 8gig microsd is max that it will accept, 45minutes =1gig.
voice activated feature 65db
standby time 250 hours
batt usage 70-90 minutes
2 hr charge with mini usb (no stupid proprietary crap) cable and stubby included
it is plug and play, the cd has a small utility to set date and time. its very small and discreet, wear it on your neck and clip it to yer shirt.