Money Tip Central has an essential list of free software (most of which is open source).
Free software can save you hundreds and possibly thousands of dollars. The software listed below is completely free, doesn’t have malware or adware, is completely legal, and I use each of them personally. Most of them are Open Source.
The list includes things from operating systems down to email applications. Check out the list and see how you can save some money for yourself and your library.