well done, for spotting that...
Legal's mate!

I managed to get this with my brother but I wouldn't risk it agaisnt anyone else.
There is nothing to risk, you only use the tactic when it works.
Legal's mate and Morphys "opera" game and the damiano opening are probably some of the more useful opening lines for beggining e4 players, these three have given me a lot of wins when I was still a begginer.

I totally love this but have never had the chance to play it on anyone. I'd have to disagree about the risk factor, it is a risk. I wouldn't attempt it unless I knew I was playing a guy with little experience. If black plays dxe5 instead of capturing the queen, the game can be pretty tough for white. White tends to get a lot of attacking play after this even though he's a piece down, but if black can find the right squares and survive he'll probably emerge in the end game with the better position. Having said that I've played both sides of this against Fritz, won and lost. Too many ifs buts and maybes involved here.
I love traps like this though, there are loads of them on youtube.
This was a pleasant surprise
I just looked at this mate recently in a checkmating book. I guess it payed off.