Ok, that's a pretty good deal. Just remember, depending on the airline and your travel habits, you may rack up some hefty ancillary fees on top of that. But if you're a light packer and don't mind a certain amount of discomfort, those cheap fares can definitely be a good way to move around Europe.

Also, don't forget to factor in transportation fees. Trains will generally drop you off in the center of town, often allowing you to walk to your hotel. Airports will require you to take a taxi or train to get to your hotel. Either can be a good way to travel. My rule of thumb is for 3 hours or less, take the train. Over 3, fly intra-Europe.