Oh yes, we're talking "a pedal-powered beer bike pub crawl" in downtown Austin for our friend's 30th birthday. All I need to tell you is that it's a big bicycle that seats a bunch of your friends, you can drink while pedaling, and you get to go to several bars. (I'll let you visit the PubCrawler of Austin website to "learn more.")
We did a two hour pub crawl, WHICH MEANS that we didn't pedal the entire time, but rather stopped at several bars along our route. (Thanks goodness - this wasn't boot camp!)
Prior to riding, I talked to some friends who were not super fans - it was too tough, too hot and made you lose your buzz. Maybe they just didn't have enough strong guys or girls in their group to pedal (not all seats pedal). Or maybe they just didn't drink enough. OR maybe they were just whining :) Yes, it takes a little work, but when do you ever get to ride a big bike downtown with your friends and drink a beer at the same time?!?! Because I had a blast and didn't mind the sweat at all.
If you get the chance, do it! At least once anyway.