JCHEEVERLOOPHOLE  Wow, an easy to use flashcard program with audio, image and video support! A beautiful yet fully functional full screen mode with complete testing options and an easy to understand history graph shows what you got right or wrong. Can be used for much more than languages, under preferences->languages just add question and answer as categories and deselect unneeded options. Many thanks to the developers for giving the mac community this amazing FREE!!! educational tool.   
(Version 4.0)

JCHEEVERLOOPHOLE  Wow, great user interface, for every task a really useful description in the status bar area shows up telling you what it does. I'm running in a limited user account and for the following uses it doesn't require my admin password:

1. Show/hide invisible files in Finder

2. Cool hidden dock preferences

3. Run dashboard widgets on desktop :)

4. Hide desktop icons. I run Blue Skies screen saver as desktop background using Desksaver Plus Widget and Spirited Away to keep visible windows to a minimum. (All programs mentioned are free and available on MacUpdate)

This program does a whole lot more but if it only did one of the four I mentioned I'd still keep it around. Cannot comment on stability, only been using it for a short while but have noticed no issues. So far, so great :)  
(Version 1.0)