One of my favorite bars has a couple of sit down arcade machines in lieu of tables. After letting Ms. Pac-Man milk me of all my quarters, I drank my beer and watched the demo screens for awhile before realizing they were rotating through a large variety hacked versions of the original.
My two favorites were Ms. Pac-Man After Dark, which turns the ghosts into neon outlines while making the maze entirely invisible, and Piranha, which pretty much eliminates all evidence of anything resembling the loveable yellow blob.