1. Rainmeter: a tiny little app that runs tiny little notification things. I use it to keep an eye on my CPU usage and temperature.
2. Circledock: very similar to what it sounds like. A VERY customizable little round dock to hold shortcuts and such.
3. Bumptop: this one needs a video to explain. CLICK. Basically (very basically) it's a 3D desktop, but an application too. It has physics.
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4. CCleaner: A small application that clears out unnecessary junk from your hard drive, such as temporary files and internet caches. First time I ran it I cleared out 4 gb. Also has a registry fixer and startup program editor, as well as a remove program list similar to windows's, minus the waiting.
5. Recuva: File recovery application, and a lifesaver. The other day I accidentally deleted the hl2.exe in Counter Strike: Source, and then emptied the recycle bin.
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If you'd like to try any of these,
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That's it for mine, does anyone else have favorite utilities? If this thread needs to be moved or locked any resident mods are welcome to.