I believe this is an eggplant flea beetle. Dozens of these tiny beetles are living on my two eggplant bushes in my garden. They are roughly 2-3mm in size, and hop when disturbed. They eat small holes in the leaves.
This is the best photo I've been able to take so far, since these beetles are so small. If you look closely you can see the muscular hind leg that helps it hop.
has some photos. Several of the flea beetles look similar, so my guess of eggplant flea beetle comes simply from the food plant. I haven't yet found a guide to help differentiate them better. This NCSU page
has a writeup.