I can't believe I didn't think of Splunk. I use the free version of Splunk as well, but I love it!
We use it with syslog-ng on our Solaris/RedHat servers for our log server. We've also incorporated all our Cisco logging, and a few of our Windows servers (with Snare). We are soon to start incorporating Apache and Weblogic logs to our implementation.
Splunk is awesome!!! Its not so intuitive to configure, but its VERY intuitive to use through the GUI once setup. The commercial version is not that expensive (depending on how much throughput you need) to boot...
eCPPT - GSEC - GCIH - GWAPT - GCUX - RHCE - SCSecA - Security+ - Network+