What's everyone's favorite and least favorite places to go in Fallout 3?

I know that my least favorite is Dunwich building, only because it really scares the crap out of me. Although, I love the reference to H.P. Lovecraft, so it's a love-hate kind of thing going on. My first play-through the game I ended up going there three times. The first time I just stumbled across it and pledged to never go there again, then I had to burn the book from Point Lookout, and then after I finished that, I realized I needed to go BACK in to get the bobblehead. It was tough.

My favorite is kind of difficult to pinpoint, although I do love Oasis. There are so many places it's hard to choose, but let me know if you've got one! :)