Posted by Compression and Caching can improve your webapp or website performance quite considerably.
A great article from David Baker can be found here for implementing Apache Compression and Caching:
http://dtbaker.com.au/random-bits/howto-enable-compression-and-caching-on-apache2.html
If you run an intranet, webapp or you run your own web server you will find this information very valuable to squeeze a little more performance out of your website.
Happy squeezing!