Last year I thought It would be nice to ride a bike the 5 mi. down past the Icicle Cr. Road washout to do a hike I've been wanting to do for a while. We were riding down a little hill and I hit the front breaks to hard (the back break was worn out, I got it on freecycle) I did a flip over the handlebars and wasn't hurt. Landed right on top of my 50 lb pack. My buddy came up behind with camera in hand laughing his ass off while I was trying to roll over with the 50 lb pack pinning me down. I felt like a turtle on his back. The picture is still up on my buddies fridge.
This year we decided to stash a bike and hike over Little Giant pass to napeequa and then over high pass on to Massie and out Buck Cr. Pass trailhead which required riding the pedal bike back to the car. My buddy (the one that laughed his ass off at me) won the bike trip back to pick up the car. Using my bike (

) where the pedal attaches it the gears some how came unscrewed and fowled it up so he couldn't pedal. For 3.5 mi. he had to push it up a hill and coast it down. I got a good laugh at that.
This fall the two of us road up the icicle again for another hike. The bolt attaching my seat came loose and the seat kept tilting backwards so it felt like I was getting raped by the tip of the bike seat. My buddy laughed. On the way back my buddies tire blew out so he had to push the bike the 5 mi. back. I laughed harder.
Moral of the story: Free Bikes are free for a reason
One of these days I'll get one of those newfangled bikes you guys are describing.