Recently happened across a TV show (?) called Firebrand--they show nothing but TV commercials, occasionally interspersed with little blurbs for their website.
There are some pretty good commercials out there, and I tend to miss most of them--first by not watching much TV, then by skipping through the commercials via TiVo. Often popular commercials show up in places like YouTube, but I think Firebrand's approach is kinda cool.
Their UI isn't quite as slick in Safari as it looks like it's supposed to be. (For example, when it says "Connecting to Firebrand Live" at the beginning, that means you're supposed to click, not that you're supposed to wait.) But not bad.
And you can rate ads, save them in playlists, email links to them to friends, etc.
I don't expect to spend a lot of time there, but, y'know, sometimes a timewaster that comes in 30-second segments can come in handy.