Packagist is the main Composer repository. It aggregates public PHP packages installable with Composer.
inflect - a memoizing inflector for php
urlify - a library for creating url-safe slugs from text
email-parse a (reasonably) RFC822 / RF2822-compliant library for parsing multiple (and single) email addresses
KRUMO - version 2.0 of print_r(); and var_dump(); (with new updates)
Hooks for using KRUMO from within Symfony -- KRUMO - version 2.0 of print_r(); and var_dump();