Spike
http://lucidmac.com/products/spike

Looks like a handy addition to the toolkit

"Rails log file viewer."

log analyzer app for rails logs

Spike is a log file viewing & (if we’re being generous) analysis tool for Rails developers.

Desktop app for the Mac that shows Rails log files.

pipe

Script lets you scroll logfiles automatically colorized making them a TON easier to read at a glance!

Logging level definition

A recent Stack Overflow post described one programmer's logging style. Here's what he logs:

Graph Visualization for Apache log files