Thanks for all the help guys. I've considered hostels, but every time I think I find a good deal on one, I start reading the reviews and they're talking about crawling over drug dealers at the door and bad neighborhoods. I almost think I would feel safer at the airport. If I knew for sure the hostel wasn't seedy, that would be one thing, of course that's the fun in hostels, right? If you wouldn't mind, I'd love to get your review of the hostel you stay in when you're in Athens, usndario.

I will be arriving a couple of nights before the marathon, so it's not like I would be sleeping in the airport, then getting up to run (well, technically I walk most of it anyway, so it's not like I'm some elite athlete or anything).

As far as transportation goes, is there Public Transportation available at night as well? As part of the marathon package, I think it's free several days before the race, although I may be coming in too early.

Thank you all for the help and advice, I've always wanted to go to Greece, and just wish I had the time and money to go exploring outside of Athens and the immediate area. Any tips you have would be welcome.