Jira - The #1 software development tool used by agile teams. Jira Software is built for every member of your software team to plan, track, and release great software.
Redmine - Flexible project management web application
Mantis Bug Tracker - Mantis Bug Tracker is a free and open source, web-based bug tracking system.
PlanShell - PlanShell offer a secure, low cost, unlimited project management & issue tracking redmine hosting services
SourceForge - The Complete Open-Source and Business Software Platform.
Collabtive - Collabtive is a web-based project management software.