I had an odd desire to quickly loop through and add UVs to a field of grass, where using instances would probably be the best choice, this particular model had all polys... Hence the script. It will loop through every visible poly in the layer select connected and UV unwrap it, then hide that group and move on to the next.

By putting a Gradient on the material for them, and applying it to UV V you can get a nice gradient on each blade of grass, or more importantly you can put an image map on it and have each blade image mapped pretty easily.. .

Depending on how many seperate pieces you have to your model it may take a long time to run (it has a progress meter however). It will also not deal with blades that are at odd angles sometimes because it uses a generic initial projection.