I'm using this user pic because I believe I'm up a creek, as they say.
I seem to have worn out the left mouse click on my Thinkpad.
It's a tiny flexible plastic hat-shaped thingie, that gets pushed in when you push the button it lives under. If you wear it out, the middle part gets torn off from the outer part and it won't give you that nice clicky feeling anymore, and more importantly, it won't work. Either it doesn't click anymore or it never stops. The latter is what was happening.
I swapped it for the one under my right mouse button, because I'd already swapped it for the one under the middle mouse button...
I'm looking for a replacement or three, but so far I've only found stores that sell complete keyboards. Not the tiny round plastic things as such.
I guess I just click too much...