first ATSC tuner in thumbdrive form but it wasn't Mac compatible. El Gato, maker of the Eye500, has our back though and just announced the EyeTV Hybrid digital/analog tuner just for Macs. The tuner is in the form of a small thumb-drive that utilizes USB 2.0 to deliver analog or digital TV to your Mac. Just plug it and go. Well, you might have to use the antenna if you aren't in an area with generous NTSC/ATSC coverage. Or you the included break-out cables will allow you to plug in an old VCR, DVD player or game system as long as you covert the signal to coax. El Gato's EyeTV 2 software is wrote natively for OS X and will allow you to record in MPEG-2 -- that is if your Mac has enough power. The tuner is currently available for $150 on their site.
[Thanks to everyone who sent this in]