In no particular order:

1. strict
2. warnings
3. Games::QuizTaker - Ok, so I'm prejudiced :-)
4. Net::Ping
5. Text::xSV - tilly did a good job with this one
6. Bone::Easy - for comedy purposes, this module is a riot
7. Net::FTP
8. Net::Telnet
9. Tk
10. File::Slurp

Some people may not consider strict or warnings as modules, but these two usually end up saving me large amounts of grief while trying to figure out why my program isn't working like its supposed to.

TStanley
--------
"Suppose you were an idiot... And suppose you were a
member of Congress... But I repeat myself." -- Mark Twain