The only gambit I play regularly is the Queen's Gambit. I prefer to sacrifice material later in the game when we're both out of book and thinking on our own. The positive side of gambits is that they help you practice yours tactics right from the get-go and that's one area most class players need to focus on to improve.
Gambiting


isn't the queen's gambit not technically a gambit?
If Black immediately accepts the gambit pawn, White can force its recapture (or play on in gambit style). But if Black immediately declines the gambit pawn and then plays the Slav (any variant but the exchange) he can take and keep it.

This is a nice collection of king's gambit ames on chessbase:
http://www.chessgames.com/perl/chesscollection?cid=1002999

Also, the King’s gambit has never been refuted. In computer championships, it’s almost always a draw. It’s not played at the top not because it’s losing, because it’s almost always a draw. Players as white don’t feel like it gives white enough winning chances.
On that other web site, you can see how it does at various ratings, and it wins more than it loses. It does as well as more “reputable” openings like the QGD. Unless you’re a GM, it’s as good as anything else.
Who here are gambiting people? I am. I sacrifice pretty much anything to win.