Git Shade (GitHub: joeytwiddle / git_shade.vim) by Paul Clark is a GUI mode plugin that adds colour highlights based on changes in Git's history. It has some configuration options for colours, and can increase the intensity of the shading with
let g:GitShade_Linear = 0.
I really like Vim Git Gutter in console mode, so check that out if you haven't seen it before.
accelerated-smooth-scroll (GitHub: yonchu / accelerated-smooth-scroll) by Yonchu makes Vim's scroll speed appear to increase and decrease, giving the illusion of acceleration you might find in desktop applications. The author has made a video so you can see what it looks like without downloading it.