to do list apps?

Anyone got suggestions for to-do list applications? I have a nice desktop calendar/event app, but I don't like the to-do list part. I'm just looking for something that I can make a list or two and leave them up on the desktop to remind me of things - something that can be printed out easily would be nice, but not completely necessary as I have an app that prints out a page that can be folded into a small booklet with lines for lists & other neat things.

Rainlendar - calendar/event
PocketMod - booklet thingy.