It looks like those might work, but they both seem to require kernels built with CONFIG_VIDEO_V4L1_COMPAT, which seems to have been taken out in the 3.x kernel. I don't have a machine with 2.x kernel that would be suitable for the heavy CPU load of doing motion detection. I might be able to run a VM or something, but it'd be a bit of a mess.

Thanks for the suggestions, though.