I saw a lot of weird shit in my days as a bartender/bouncer. And I'm here to tell you, if some guy wants to bet that he can piss in his own ear from twenty feet away, don't take that bet. You'll be buying drinks for a guy whose earhole smells like piss for the rest of the night.
There are guys out there who have developed some weird, goofy skill, perfected it, and take it to bars and use it to get drinks, money for drink, and their own personal amusement.
Here's an example, and was the first and last time I ever got taken:
The appeal is to pride (as are most of their tricks) and I was a young, prideful man, who still hadn't learned that I didn't know it all. This fellow got all the dice from the horse cups, put one down in front of him, tore the top cover off of a book of matches, placed it on the first die, and then stacked the rest of the dice in a column on the matchbook cover.
Then he bet us that he would pay $100 to anyone who could get the cover out and not knock the dice over. Simple, right? Oh how we tried. And the dice kept rattling on the bar.
You see, we tried so hard because the bet was, if he could do it, we owed him $100. Each.
Finally, we gave up, and told him okay, smartass, let's see what you've got. So he walked up to the stack of dice, and flicked the matchbook cover out with a quick snap of his middle finger. The cover flew out, and the dice didn't move. To say that we were dumbfounded would be an understatement. We paid up. You do NOT welsh on a bet.
That incident, and many others I've seen, and a few I've done myself, has made it to where if you tell me you can, or will do something, I believe you, until such a time as you prove yourself to be just another bullshitting blowhard.