Something's up with my seatpost. It keeps slipping downward. Any ideas how to fix it? The bike is 20 years old. I'm thinking of removing it entirely, cleaning it with a good solvent, and then putting it back in.

Or I can use it as an excuse. "Honey, my seat keeps falling down. I need an <insert expensive bicycle> ASAP!"

The lower seat works the tops of my quads though.