Ohhh... now I'm hungry...
I make my own burgers - medium rare on the grill. I mix seasonings and some A-1 into the beef - they come out nice and juicy.
When I was in school, I used to eat at a burger place in Harvard Square (I'm blanking on the name) that makes really good burgers. They had several unusual offerings, mostly named after celebrities... the only one I can remember offhand is the Madonna burger, which is topless! (no top bun)