Troggie is an IRC Bot that was originally written to implement Factoids, the main feature of infobot. It quickly expanded to include several useful plugins such as a last time seen plugin, displaying titles of URLs, weather lookups, Google search/translate/calc, along with a few lesser ones.
PircBot is the base IRC library. Troggie was originally written in Java using Apache Derby (now JavaDB). It then was migrated to SQLite for the reduced memory footprint. Now it's being rewritten in Scala using Akka for better concurrency (and to increase my Scala proficiency).