Bug Tracking Software
Here is list of software that can be used for bug tracking or issue tracking. http://www.redmine.org/ RudyOnRails, lot of features. good one http://www.bugzilla.org Perl, bug tracking only. Very popular, large projects use it. http://trac.edgewall.org/ Python, popular, i see many medium size project use them. http://www.mantisbt.org/ PHP MySQL http://flyspray.org/