Best moment ever - my buddy and I beating Super Contra in a video arcade. The version in our arcade was japanese, the only words we could make out is "Super" and "Konami".
If we had all of the quarters we dropped in that machine we could have each bought one. There was a crowd of about 25 people watching when we beat it, totally felt like a rockstar. We had every top score on the machine, no one else played it due to it's difficulty, you had to have two players working together to do anything.
Totally worth it.