The SitePoint PHP blog has a post from the godfather of the PHP community Cal Evans about paying the price for open source - giving back to Open Source projects that you use every day.
Back in the early days of Open Source – when Dinosaurs roamed the earth and Rasmus was a young man – there were two types of open source projects we talked about: those that didn’t cost any money, and those that gave you the freedom to redistribute and modify the code.
[...] Fast forward a few dozen years and here we are, Open Source is now an ecosystem, not a user group that you and five friends attend, or a magazine to which you subscribe. The problem is that most of us have stopped talking about the different types of open source, we just assume it is both.
He talks about how PHP is technically both kinds of free but also points out that open source will potentially die out (as it is now) without one major piece - users contributing back, giving their time and effort to keep it (and related projects) free. He talks about how you can give back, and not necessarily monetarily. He talks about one of his own experiences with giving back (to WordPress) when his work wasn't accepted, but he also points out that even though it may be rejected it doesn't mean you should stop.
What ever project you are working with, take the time to give back. Don’t let Open Source die in our generation.
Preserve this great concept; this ecosystem that we have helped build and that has allowed us to build so much. If you are a developer, find your favorite project and give back. If you run a company or a team of developers, give them time on your dime to give back to a project. Help keep the Open Source ecosystem thriving for the next generation of developers.