WpPygments is the plugin that utilizes Pygments library (through the http://pygmentizer.appspot.com service, which I also wrote) to highlight and colorize the code snippets in your WP blog.
Plugin page: http://blog.mirotin.net/wppygments
Plugin code: http://github.com/emirotin/WpPygments/
Pygmentizer service: http://pygmentizer.appspot.com/
Pygmentizer code: http://github.com/emirotin/pygmentizer/
As usual - unzip the archive to your plugins forlder, go to WP admin panel and activate the plugin.
You can set several options:
theme -- pick one of the existing Pygments themes
tools -- set which of the existing tools (view raw code, copy to clipboard, print) you need
cache clearing -- set how long code highlighting cache should be stored (since the last access time)
Configuration is available as a separate WpPygments page under the Settings menu.
With PG4WP cache is not working (looks like plugin<->DB communication is broken at all for all plugins). This means, code will be re-submitted to pygmentizer service every time the page is requested. I should say, it doesn't significanlty slow the page (tested with the page containing 10 small pieces of Bash code).