FeedThingy is a feed reader written completely in JavaScript. It uses several new and emerging browser technologies to create an application that runs entirely in your browser.
FeedThingy allows you to create rules based on keywords or patterns (regular expressions), these rules are used to assign each post in a feed a score to help you find posts that interest you and deemphasize posts you probably aren't interested in.
Presently, this application is only guaranteed to work with recent versions of Firefox; in theory it should also work in IE10 but has not been tested. This is because it uses bleeding-edge technology (IndexedDB) which is still in working draft form and not implemented fully in most browsers. Every browser implements new versions of the draft at their own pace so major changes in the draft may break the site if the browser you use does not keep up with the current version of the spec. Google Chrome does support an older version of the spec, but it is not presently compatible with the current version of the spec. For now, Firefox is the only officially supported browser as it is the browser used to develop and maintain this application.