GitKraken - The intuitive, fast, and beautiful cross-platform Git client.
Deck - A multi-timeline viewer for GitHub repository events
SourceTree - Mac and Windows client for Mercurial and Git.
DeckHub - A TweetDeck style desktop client for GitHub.
GitHub Desktop - GitHub Desktop is a seamless way to contribute to projects on GitHub and GitHub Enterprise.
JXL for Jira - The power of Jira with the familiarity of spreadsheets