Please recommend good ClickStream analysis tool

[Jessica Zhu]

Hi, 

We are trying to find a good ClickStream log analysis tool now. Our web 
log size is ranged from 300MB to a little bit over 500MB. I need to find a 
tool which has good drilldown ability, easy and friendly interface, and 
can be scalable enough to handle big volume of log file and can run on 
Red Hat linux platform.

Any input is welcomed.

Jessica