Just an amateur and enthusiast. By day I play a mild-mannered financial professional in Japan. Here are a few of my side projects:

• FinAnSu - An Excel add-in allowing the import of security quotes and web data in general, along with functions for option pricing, parsing CSVs, sorting data, interpolating rates, quicker access to accounting formats, etc.
• Rupee - A financial library for Ruby
• Konjac - A Ruby command line utility for translating documents using YAML dictionaries
• Prisma Quotes - A Chrome extension to get live quotes and charts for stocks and securities from Bloomberg, Google, Yahoo! and Quote.com.
• akamon-ec.org - The site for my club at University of Tokyo.
• yaku - A reader for the excellent EDICT dictionary.
• transcripa - Transcribe some languages into IPA.