Originally Posted by Velo Dog

There's also a Murphy's Stationary Biking Law. A couple of months ago I had some surgery, and a friend gave me his old stationary Diamond Back to use during rehab. he's quite a bit shorter than I am, and the seat post was stuck where a 5'6" rider would use it. Adjustment was obvious, just pull the pin and slide it up...
Wouldn't move. Would NOT move. I fiddled and hammered and shoved and WD-40ed, and I couldn't get it even to wobble like it MIGHT move. Finally I gathered some tools, planning to pull off the plastic side covers to see WTF. I laid out the tools, got painfully down on the floor next to the bike (knee's still pretty tender), and, just for fun, gave the pin a two-finger tug. It slipped out with about two ounces of pressure, and the stuck seat post rocketed down, letting the saddle hit me in the head, then slam my fingers.
Works fine now.