A while back I blogged about doing a PMD check of several large open source projects. The article I wrote about that has now been published in the June 2006 issue of StickyMinds' print magazine - Better Software. It's a feature article and the layout looks pretty nifty; nice swirls and colors and whatnot. Looks like they have a free sample thingy on there too, so if you're interested, you can order one up at no cost.
The article itself was fun to write. It was nice to have a chance to poke around at the various things that PMD and CPD turned up in such large codebases. Hopefully I made the point in the article that Azureus and Columba are both good, successful projects, but even such projects usually have a few problems that a static analysis tool can find.
I thought about writing up patches and sending them in to those projects, but I hate to be one of those guys who just flies in, drops off a patch, and leaves. But if anyone from those projects is reading this, you can check out the reports that I put together for the article. And of course you can always post any questions or whatever to the PMD forums.