Linky is your friendly intranet URL shortener. Its made to be simple to setup, simple to use, and simply useful. Linky is based off of a number of internal URL shorteners that exist in many large tech companies in the Silicon Valley.
ObStore is a smart persistent Object store for ruby. It allows you to persist any ruby object to disk for later. It also provides functionality automatically expiring objects from the ObStore database based on time.
(great for caching stats for monitoring services)
A simple, dirty, & lightweight ruby HTTP client gem. HypeText supports GET and POST functions. Its designed to be a lightweight and easy-to-use HTTP client when all you need to do is a quick little HTTP call in your code.
The IRC bot framework gem. Spunk was inspired but Sprinkles but takes it a few steps further (mainly because Sprinkles appears to be abandoned). Spunk makes it dead-simple to create an IRC bot or script.