I just wrote git diffn, and need some help testing it since I don't have Windows. If someone can try it out please, I need to know if it works and a full set of install instructions. Start with my writeup and install instructions here: https://stackoverflow.com/questions/24455377/git-diff-with-line-numbers-git-log-with-line-numbers/61997003#61997003
I think it's pretty useful and I'm pretty excited about it. Check this out. It shows line numbers!

It relies on gawk, but if gawk doesn't work in the Git for Windows bash terminal I can make some modifications I think and make it work with regular awk.