Thank you, Ocicat.
I'd like to point out that we who give back to the Project do so in a variety of ways.
Funding - always a critical need. Purchases of the CDs and monetary donations are two of the best ways for individuals users to contribute.
Testing - I listed several types of testing as an advantage, above. But the advantage is two-way, since the Project also benefits. Ports testing is the easiest way for newer users to contribute technically. New ports are posted to the ports@ mailing list constantly, and your feedback to the port developer/maintainer would be deeply appreciated, whether it is formal or informal. Ports testing is easy -- there's even a
Ports Testing Guide to help you. This is a low-cost way to contribute, as it costs you nothing but time.
Hardware donation - There's always a need -- see
http://www.openbsd.org/want.html for what developers are currently looking for.