We're currently working on my bachelor's thesis on the subject of why people give up their free time and work on open source projects. As a first step, we're collecting data on the motivations behind it.<p>There's just one question on the form, but please write as much as you have time to! Thank you!<p>https://docs.google.com/forms/d/1MtXwd4kVF6kSuC4q_4rDaUksBRckLaCfgJGP6_JKSnY/viewform
This old discussion on the Programmers StackExchange might be of interest -
<a href="http://programmers.stackexchange.com/questions/3233/why-do-programmers-write-closed-source-applications-and-then-make-them-free" rel="nofollow">http://programmers.stackexchange.com/questions/3233/why-do-p...</a>
It's not always free time. At companies I worked for, we upstreamed open-source changes, because we wanted to shift the burden of maintenance.<p>But I sometimes have similar motivations for contributing my changes to open source projects privately, too.