PC World: Despite the wealth of free applications out there, many small business owners continue to spend an inordinate amount of their all-too-scarce resources on software. Microsoft Office 2010? That'll be $499.99--or $279.99 if you can do without the Professional version. QuickBooks 2010? $159.95 or more. Adobe PhotoShop CS5? A whopping $699.

The good news is that there are free and open-source alternatives for virtually every package a small business might need, and most of them are excellent. Whether or not you've already made the switch to Linux -- there are, after all, myriad security and other reasons for doing so -- these free apps can be just what any small business needs to succeed.