Here is a patch for pngcrush.
We have optipng which has better compression/quality than pngcrush.
I compiled for my own purposes, so that's fine :)
@DataDrake I couldn't get optipng to get to a decent size, pngquant did wonders.
@Justin not that I care if optipng gets included, but it's lossless, while pngquant is lossy. Also, zopflipng yielded the best (lossless) results in my testing, though last I checked it was not packaged on Solus.