pngquant Photoshop plug-in

It provides PNG saving better than Save for Web. Typically creates PNG files 60-70% smaller than 24/32-bit PNG from Save for Web, and unlike 8-bit PNG from Photoshop, always supports semi-transparent alpha channel.

• Download for Mac OS X and copy pngquant.plugin to /Applications/Adobe Photoshop C*/Plug-ins/.

• Download for Windows (SuperPNG plug-in)

To use it choose regular Save As and PNG for Web (pngquant) as the file type. A small web-optimized PNG file will be written without any prompts.