I use List::*Util on a daily basis, so this module is great. Typically ends up as a requirement for most of my modules.
This should be renamed the Date::Awesome module. Much, much better than that localtime stuff in core Perl. Date::Parse will parse absolutely anything close to a date string, yet it's smart enough to know to not try to parse, say, times in sentences.
Another excellent Graham Barr module.
This module is better than Peanut Butter! I have entire essays on why stuff like warnings and taint control are annoying, and this module fixes all of that.
Use common::sense... always!