An important part of being successful in using computers is finding the right software, which does not necessarily mean having to buy it. This 
shows around 55 programs that are mostly freely usable, and tells about their functionality, and gives tips for usage. I use a lot of them already, but even I heard about a few extra!
Of course you doi not need to go for the freebies, and lots of packages allow for donations if you feel you have to contribute, but I guess open source developers mostly are in it for the love of their product, and they realize that doing good while enjoying yourself is the best way to live a great life. If not directly appreciated in cash, they know that life will provide anyway.