For those who don't know the post-it note programs, let me explain a little bit. It is like real post-it note papers. You can write small notes on it and you don’t need to save it when you shut down your PC. When you run that program next time, the notes u wrote will still be there.
Actually, there are many programs like this. There are some in "Yahoo Widgets" (Konfabulator) which are really awesome. But this “Quick Notes" is so simple and light. I have been using this small program since long time ago and I even made a skin with matrix theme.
Original site, lowdimension.tsx.org, is down but you can download it here. It is free :)
PS: I removed other skins to reduce file size. But the skin I made is the best. Trust me. :P