Any startups have experience with Splunk? Seems like it might not be too expensive if you're not massive, and some of their demos are impressive. http://www.splunk.com/
I've found that it's great for a sort of RAD tool, but the functionality ends there because licensing and scalability are so expensive. The other problem is that it's so generally purposed that it reaches a point where integration with existing sort of FCAPS compliant setups is more of a chore than anything. Best put, it sort of reminds me of a Oracle Application Express for logs. I can do most anything with it quickly to get a good handle on things, but in the end I'm going to take those ideas and make something better with them.