YouTrack from JetBrains - customizable yet easy to use issue and bug tracker

A keyboard-centric issue and bug tracker, allows you to: - Enjoy extensive keyboard support. - Search for issues using intuitive query syntax, aided by intelligent query completion. - Modify multiple issues at the same time from the command window. - Create and manage custom attributes. - Import issues from any bug tracker and perform batch operations via REST API. - Import existing issues from JIRA 3.x- 4.x. - Set access permissions per-issue