The Hack MySQL Kit contains scripts which help analyze and troubleshoot MySQL: mysqlreport, mysqlsla, mysqlidxchk, and even mysqlsniffer.
http://hackmysql.com is the home of all these scripts, but now their code is centralized, revision-controlled, and issue-tracked here at Google Code for the convenience of other community developers.
Full documentation, all the guides, and other MySQL-related information is available at http://hackmysql.com/.
These details are provided for information only. No information here is legal advice and should not be used as such.