Quail is a real-time log viewing program that I wrote to support large files with color highlighting and search functionality. Quail also provides a front end to LogParser enabling SQL query support for your logs.
Screen Shot of Tail View
Screen Shot of Query View
Download the source code | Download the executables
Quail is written in C# and has some interesting code to tail logfiles, search, use a virtual listbox with colors, read options, and put a GUI on LogParser. To use the query functionality you must install LogParser 2.2.
-Enjoy
If you find bugs send me a line...
Update (2/25/2006): Fixed bugs around display issues, key handling, and file reload on log rollover.
Update (5/22/2006): Enhanced highlight feature and added load from non-working directory.