I use 1.e4 e5 2.Nf3 Nc6 3.Nf3 f5.
3.Nc3 is a Vienna gambit and 3...ef is best although here you have much easier defences than against the normal king's gambit.
There's also 1.e4 e5 2.f4 d5 3.ed c6 but White can get even endgames easily if he wants.
Just out of curiosity,
Is there an aggressive chess opening as black against e4 which is llike the kings gambit. I know about latvian, but there Nxe5 is possible, so anything else?