I think that open source software (with license agreements that let me use it in commercial applications even if it means contributing my changes back) is great. We use it extensively in my work and have contributed back our changes as required in one component. Another component we use has proven to be a constant thorn in my side that I’m almost at the point that I’m going to scrap the code and write it myself; however, it does stuff that I don’t know how to do. I’ve had to fix this particular bunch of code twice in the last week. On a positive note, it keeps me employed.