TV IV
It was mentioned on slashdot a few days ago, but TV IV really is something that needs to be checked out.
It is trying to be the Ultimate TV guide, but in a wiki format so everyone is able to contribute and add their own ideas to it.
It's a great idea in light of services such as TVTome disapearing (even though TVTome did reappear as TV.com, run by c|net, it isn't as good as the old verison).
