Git

(assuming that "bc" is aliased to be active instead of the command line calculator,

using beyond compare for git differences:

# setup

git config --global diff.tool bc
git config --global difftool.bc.trustExitCode true

 
# use for a single file, will prompt for "really wanna use beyond compare?"

git difftool file.ext

# use for the entire repository directory structure, no prompt

git difftool --dir-diff