Given that it took me a long time to figure out how to get a good compression chain working, and even longer how to correctly host the resulting pack200’ed applet, I thought I’d distill what I figured out into an easy-to-use package. Hence, I present you 4kForge: http://www.zarkonnen.com/4kforge/
Once installed, 4kForge lets you compile&shrink your game using a single shell script invocation, and start a server that hosts the resulted .pack.gz with another. 4kForge is available in Linux and OS X flavours, and comes with no warranty of any kind, or guarantee of correct functioning, or guarantee it will not go back in time, kill your grandfather, and cause you never to be born.
Special thanks to pjt33 for his Zip2Gzip and HTTPD programs that make this possible.