I have an objection to software costing more than it's worth.

OpenOffice.org allows me to write all my university assignments, create all of my graphs and manipulate spreadsheets.

It cost me $0.00

Ubuntu allows my computer to operate. When I installed it, instead of taking the time to remove a number of applications to clean up what should be a a clean install (windows I am looking at you), I went to the Ubuntu forums, where I was welcomed and aid was given whenever I asked.

It also cost me $0.00

GIMP - I'm no professional photo editor. I used Photoshop to touch up and otherwise screw with photos. I have no idea of the differences, but I have not noticed any less functionality.

It also cost me $0.00

Amarok - even better than Winamp.

It also cost me $0.00

Evolution. Outlook sucks.

It also cost me $0.00

Eclipse - Cross platform application development. Compatible with a huge number of languages including Java 6.

It also cost me $0.00

VLC

It also cost me $0.00

With all this high quality, user created software available for free, I couldn't rationalize continuing to use Windows.

Side Note:

A month ago I decided to install a virus scanner, just for a laugh. It found 3 viruses during its first scan - all of which were Windows viruses located in my WINE directory!

Well I thought that was funny.