Recommended for viewing on Hulu:
1. The first 3 seasons of Buffy. Fun times.
2. The first season of Angel. Even better than the first 3 seasons of Buffy (which I certainly wasn't expecting).
3. Journeyman. Never heard of it before, but I looked around for good sci-fi shows on Hulu, and this one had good ratings. More importantly, it's actually good. It's set in 2007, and involves some time travel, and what happens to real life when you inexplicably pop out of the present and into the past. When you're done in the past, you pop back into the present--hours or days later. I liked it more because it's a good show than because it's sci-fi, although the sci-fi element doesn't hurt it. I like that it struggles with the messiness of relationships and work and family, and how they conflict with the time travel. Unfortunately, some of the struggles are solved a bit too easily (perhaps because the writers found out the show would be canceled after just one season, and wanted to wrap up loose ends, or perhaps just a weakness in the storytelling). In any case, despite that one small weakness, I recommend it. And it's not as PG-13 as Buffy or Angel.
I've also watched the first episode of a number of shows I didn't care for (including Pretender and Eureka).
Now, I've got to find a way to borrow the rest of Buffy and Angel...
Any more recommendations for great TV shows?