Konfabulator
Remember back in the old days of OS8-9 or so, you could make your Mac look and do just about anything. There was always SOME hack that you could put in your machine, some extension that delivered some enhancement or feature that made your life better in some strange way. OSX did away with all that, because along with the little widgets such as Zipple and Before Dark came instability.
Now along comes Konfabulator, stable as far as I can tell, and truly a welcome addition to a Non-Customizable Operating system. Yeah!