I once made $20 chugging free 32oz Big Beers at Tubby's because one of the regular riley rats challenged me. (This was at noon on a sunday while working)
Started out that the bartender poured the wrong beer, sent it back to the kitchen. Guy sitting at bar says $5 you can't chug that in 45 seconds....please. Took it easy and downed that sucker with time to spare.
10 minutes later another big beer shows up, same deal but 30 seconds this time....puh. lease. Knocked it out. Even had time to do a couple of push ups before finishing, just really rub it in.
15 minutes later another big beer shows up. Double or nothing but this time I only get 15 seconds. No problem. Boom. $20. I'm rich.