There are lots of programs that simulate sticky notes for your computer. Windows 7 even comes with one built in. And I've just figured out why I don't like them: you only ever get as much space to physically arrange them as you have on your computer desktop. It's as if someone gave you free reign to write whatever you want on an infinite stack of index cards, and arrange them however you want, but only within a tiny little tray. As soon as you try to store any decent amount of information there, you'll run into problems.
Scrolling and zooming are hardly new concepts in software, but apparently these sticky note programs haven't caught up to that point yet.
Mokalus of Borg
PS - I'm sure I'd lose track of some of my notes on an infinite canvas.
PPS - So maybe it's not the final answer.