git-cola
Git-cola can compare arbitrary commits using standard merge tools. With it you can search commit messages, content, authors, paths, data ranges etc. and it makes it easy to interactively edit the index.
Latest reviews
Not much to look at, but it's functional, fast and not a lot of hassle to start using. I've been using Sourcetree on Mac, and have been searching for decent alternative on Mint for a while, and finally, felt at home here. Only complaint so far is that the History view is a separate window.
One of the most feature-full graphical frontends for Git currently available.
I don't like this, It's better to learn some cli code and do things manually in a terminal
I have found this to be a very useful Git GUI client. Easy local operations as well as pushing/pulling from remote sources (e.g. github).
Good tool for git integration. Very handy for n00bs who haven't got the hang of the command line yet. Some room for improvement but perfectly adequate for most purposes
SmartGit is a much better option if you want a GUI for Git (http://www.syntevo.com/smartgit/index.html). Git-cola has useful functions, its just that they are presented in an even nicer GUI with SmartGit.