Project Dogwaffle comes to mind, if on Windows. www.dogwaffle.info

PD Pro 5 just released a few weeks ago, still on launch promo till end of October (Halloween, where prices go scary high)

There are others, you could find some at thebest3d.com (same as dogwaffle.info)

Some are free, some are very good, a few are both.

What do you need , something for very small sprites?  Below 31 pixels across?

Dogwaffle is better for mid and large sizes.