Chuck Wood (of LPOD fame) and some colleages are putting together a MoonWorld virtual reality simulation on Second Life. They will be using actual topographical data to recreate at reduced scale the crater Timocharis. Avatars on Second Life will be able to teleport to a lunar base, don a spacesuit and explore the "lunar surface". Next best thing to being there, I suppose.
Today's LPOD describing the project:
More detailed description: