Rice Gambit.
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Damiano gambit is really good with 1. e4 e5 2. Nf3 f6 3. Nxe5 fxe5 4. Qh5+ g6 5. Qxe5 forking the king and rook or 4. Ke7 5. Qxe5 Kf7 6. Bc4+ d5 7. Bxd5+ and either 7. Qxd5 8. Qxd5+ or 7. Be6 Qxe6#
My opinions: Cochrane gambit is almost sound. There are gambits for both colors in the Tarrasch QGD that are also almost sound. Schliemann's soundness depends on the opponents memory. I'd say it is sound for 99% of human players. White has a piece countergambit in Schliemann that is has a thin line that refutes it but was sure fun to play before computers found it! In the classical defense to Ruy, the 5 d4 line has [if I recall correctly] a gambit subline that always seemed sound to me.