One of the best examples of Open Source software I have found is Audacity.

Audacity offers the ability to create multitrack recordings, which is great for musicians. It also can convert its own files into mp3 format to be shared. The software will also generate tones, which I used as I was developing a tutorial on music theory. I have also used it to create spoken-word podcasts for classes I teach. Sometimes Open Source software can be unstable, but Audacity has been around long enough that the bugs are pretty well worked out. Also, while there is a secondary file that must be downloaded and then “found” by Audacity (a common procedure in the use of Open Source software) in order for some of the plug-ins to work, the instructions for doing this are clear. If you are considering learning how to use recording software, Audacity is a great way to get started. It’s good enough that I use it exclusively for my recording needs. And it is a great way to get started using Open Source software for lots of different purposes.