The first two times my wife an I were in Vegas we played these nickel slot machines at the Bellagio which featured a bonus spin if you hit a special combo. The bonus included a caveman making funny grunting noises and a choice of three payout offers. Sadly, the last two times we were in Vegas, we couldn't find these machines. We know they are old because the first time we played them probably 2004 we were still using actual nickels. Anyway, if anybody has seen these around Vegas, please direct me to them, they were so much fun and particularly lucky for us during those trips.