In my particular case it's the mysql general log and slow query log; neither is critical to operations, just there for troubleshooting if need be, and mysql doesn't have a mechanism for rolling or truncating either of them. These logs can grow ridiculously large if neglected. Is there a nice little cron-job+bash-script hack for rolling or truncating these files? Thanks.
Assuming Linux/Unix, logrotate
See: http://www.cyberciti.biz/faq/how-do-i-rotate-log-files/