I've always wanted to ride on the upper deck of a 747 either 200 or 400, I don't really care. The girlfriend and I are trying to decide where to go on vacation this summer and I'd like to go on a 747. Any suggestions for a nice vacation spot that NW runs a 747 on that won't eat a bazillion ff miles?

Or if all else fails, what's the cheapest way to get up there?