Twinhan USB TV Tuner for Mac (free upgrade to EyeTV 3)
An external Digital HDTV tuner with EyeTV 2 software for the Mac. Can be upgraded for free to EyeTV 3 here:
Apparently you need to scan your receipt to prove purchase to get the upgrade.
Clearance sale. Reasonable shipping charges (cost $12.70 to Tas).
Although that's not cheap by Windows standards for the tuner, EyeTV 3 by itself is $81 for an upgrade and $162 outright! Far better than any Windows TV software I've seen (except maybe Media Centre).
The tuner also works on Windows computers (but doesn't come with Windows software).
I'm getting it just for EyeTV.