At my last job, I was a strong supporter of using an issue tracking system to help coordinate bug fixes and features. The projects were internal only, and since I'm a big opensource nut, I pushed to use scarab as our issue tracking server. The supported features were adequate, and the speed wasn't horrible, so life was good.
Now that I've established several open source projects of my own, I decided to give JIRA a try. It didn't take me long to see that JIRA is hands down the best software out there for issue tracking. I got my instance up and running in a matter of minutes, and haven't had to touch it since. Plain and simple, this software rocks!
Since development on scarab seems to have come to a screetching halt, I wonder how many people out there are moving to commercial issue tracking software, or if there are other good opensource solutions? And I don't want to hear anyone mention Bugzilla!