This is mine. Totally a blast going through all the old faves. 1941, bubble bobble, contra, donkey kong, dragon's lair, double dragon, elevator action, gauntlet, ghosts and goblins, off road, kid niki radical ninja, marble madness, 720, shinobi, narc, rush 'n' attack, spy hunter, super mario bros, NBA jamz, tetris, and track and field have been my favorite arcade games to play lately.
NES has some classics as well. I've hit up SMB, zelda, metroid, kid icarus, tecmo bowl, RC pro-am, bionic commando, castlevania, ice hockey, excitebike, megaman, gradius, punch out, metal gear, and wizards and warriors lately. There are crappy NES versions of wizardry and Ultima although they can't beat the old apple 2 Proving Grounds of the Mad Overlord and Ultima series, which I played relentlessly as a kid.
Nothing beats gathering a few dudes and a few (dozen) beers and mashing buttons until the wives start freaking out. They like to comment that our average "guys' night" is more like a junior high sleepover than a bachelor party.