I have found the following utilities useful and hope you will too.

UnReply
A text editor designed to sort out text that has been mangled by e-mail.
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Open Office
OpenOffice.org is a multiplatform and multilingual office suite and an open-source project. Compatible with all other major office suites, the product is free to download, use, and distribute.
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AdAware
Anti-spyware software.
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AVG
One of the best known anti virus software.
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LogMeIn
LogMeIn Free gives you the flexibility to access and control your PCs from anywhere.
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Unit Conversion Utility
Unit Conversion Utility is a utility which allows the easy conversion between a variety of metric and imperial units.
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Winzip
Zip up those files to make them managable in size.
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