Rancid's good. Also look at CatTools from http://www.kiwisyslog.com/kiwi-cattools-overview/ for a similar windows tool. Free for small networks, ~$550 for networks over 20 devices.
"I just want to be a good engineer." -- Steve Wozniak, co-founder of Apple Computer, concluding his keynote speech at the 1988 AppleFest