The budapest gambit is an opening played by black against the queen's gambit. This opening gambits a pawn to get good position, traps, and often equalizes in material.

right now I am trying to learn this opening. When I thought I begin to understand it, I challenged a player rated here above 2100 and he showed me that I still have quite a journey to overcome :) here are the games (still in progress, but unrated):

http://www.chess.com/echess/game.html?id=56179024

http://www.chess.com/echess/game.html?id=56179008

http://www.chess.com/echess/game.html?id=56171170

feel free to comment.

Rated or not, it is not appropriate to comment on ongoing games.

I just love this to play against d4.  The smothered mate checkmate is very satisfying to pull off if you opponent blocks the bishop check with Nbd2. Doesn't happen a lot, but I've been lucky enough to pull it off twice in blitz.  If it's not too much hassle, Koala8, could you post that one so people can see just how fun the Budapest Gambit can be!!  I'd do it myself, but I'm still not sure how you guys do that, lol. H.G.

The only thing i don't like is that white has an option : Qd4

In all my 30 years playing the Budapest, I don't think I've ever encountered 4. Qd4.

If you meant this smothered mate already posted it on the first post in the parenthesis.

and your problem with the posting it's the first icon in the top left of the comment box and I've found out that it only appears on the computer (not the ipod).

Thanks a lot, now I know why I missed it the first time!!!!!!!

What I hate about this gambit is at my level people don't always play the queen's gambit after d4

I hear you on that!!!! I stated the same thing in the thread someone opened about what to play against d4.  After Nf6 nobody seems to wants to play c4, lol.  I don't know if it's to avoid the Budapest, but I doubt it.

I made a numbe of experiments with the Budapest Gambit with black in OTB tournament games 20 years ago. The tricky thing for black is:

One error in the move sequences and you are dead !!

I don´t think the BG is a useful tool for OTB tournaments. Better spend your time with a more solid defense against d4 (Semi-Slav, Nimzo, Grünfeld, KID, etc.)

Maybe it isn't entirely sound, but it can work against quite strong opposition, at least in rapid chess:

http://www.chessgames.com/perl/chessgame?gid=1487852

Anyone could post a game where white plays 4.f4 instead of 4.Bf4? 

Is this opening generally considered sound?

And is it a true gambit, or can the pawn always be recovered with proper play?

Formanek was still a 2400+ player when I played him, but he handled me easily enough, too.  I played one of my own innovations on him in the French, and he demonstrated its limitations rather piquantly.

4 Qd4 just can't be any good. It does have a spot in the 4th move alternative section of Chessbase's Big Key, but in my database of master games since 2007, out of 246 Budapest games not a single one saw 4 Qd4.  Since rooperi's trap means she can't grab on g7, the Queen will have to lose time eventually retreating after ...Nc6.  It just makes no sense.

Maybe he played Qd4 just to get out of book so he doesnt mind losing a few tempos?

Probably you are correct.  In the given position, it will be hard for Black to exploit his development edge, and once White catches up it is a new game. 

And it's not a bad strategy generally if you suspect you are being invited into some pet line, just opt for an easy equality that isn't often played, putting both players back on their own.

Another Budapest trap: