I'm not a big TV watcher. I've never owned a TIVO, I get the barebones cable with a few HD channels for about $25/month.
But, I did get a Sony 42" XBR TV this year and wanted something to take advantage of it and my iMac's 24" screen.
I've got the EyeTV Hybrid plugged into my iMac and a cable outlet. Without a cable box, I pay nothing for that extra cable connection.
Last night I recorded Lost episodes that were running back to back while watching a DVD on the TV. Nice. Full quality for this 3 hour program was 16 gigs. Not a problem with my 500 gig drive.
The recording looked awesome on my iMac. When I get an AppleTV, I'll try watching there.
I exported the recording to iPhone format and will be trying it out on my iPod touch. That 3 hour file will take up a little over 1 gig there.
For $100, this EyeTV Hybrid totally rocks!