I've really enjoyed working with sheet metal in recent years. It's really satisfying to start with just a sheet of say, 18guage steel and some mallets and hammers, and shape something useful or beautiful from it. If you've got a hankering to try your hand at metal fabrication, take a look at some of the resources available from Amazon and Amazon Supply here.
I have some Martin body hammers and dollies, very nice tools... high quality stuff.
Ron Covell is a great teacher in this arena. He has various books and videos out there, and he holds seminar classes around the country, too.