1. Permanent recordsRails Plugin - soft-delete your ActiveRecord records. It's like an explicit version of ActsAsParanoid
4. alphadecimalBase62 encoding and decoding to turn numbers into very compact strings
5. shawty-serversuper-lightweight url-shortener designed to run FAST on Heroku.com
6. hsqlStore a hash of data with your SQL queries
8. dotfilesJack Danger's ridiculously optimized terminal