One thing that has bothered my about git was the lack of tab complete. Well,
this was completely my fault. It turns out that in the git source tree in
their contrib directory is tab complete bash script! Here is how I installed it and
made my life 75.6 times easier:
cd GIT_SRC/contrib/completion
cp git-completion.bash ~/bin
echo "source ~/bin/git-completion.bash" >> ~/.profile
source ~/.profile
Viola.