My OSS Ruby on Rails applications:

RecipeTrees - source (https://github.com/nazar/recipetrees), site (http://receiptree.com)

A recipe database but with a twist: users can fork recipes for alteration; all forks are tracked via an acyclic graph. Other features: nutritional value calculation and inclusion of recipes within recipes. Stopped coding in late 2011.

Parlmnt - source (https://github.com/nazar/parlmnt), site (http://parlmnt.com)

Parlmnt scrapes Legislation information from http://parliament.uk and presents it in a more debatable manner. Provides data via a JSON/XML api. This is mostly a Backbone.js application. Still coding but is in early alpha. Helpers welcome.

MediaCMS - source (https://github.com/nazar/MediaCMS), site (http://pantherfotos.com)

A commercial media library supporting: photo/video/audio uploads with background processing with large format support. E-commerce mechainsms available for media up-loaders (i.e. price per image size, audio sample rates etc). A large Rails project clocking in at about 17,000 LOC. Stopped in early 2010.

DarkFallSage - source (https://github.com/nazar/DarkFallSage), site (he's dead, Jim)

DarkFallSage is a WowMaps type website aimed at the DarkFall MMO. Features: custom Google Maps tiles that use the game world map to overlay loot/mob information; mob/loot database; support for clans public/private forums; skill trees; discussions on each game item/skill. Stopped coding in 2010.

Waster - aka TheLastBunker.com - source (https://github.com/nazar/wasters), site (she's dead, Jim)

Wasters was aimed at the Fallen Earth MMO. Wasters was developed to catalogue crafted items, not too dissimilar from the Bill of Materials shipping problem. I re-invented the wheel on this one by figuring out the Materialised Path pattern. Stopped coding in 2010.

Live long and prosper.