Used by http://labs.techbrew.net/wordle to extract significant terms from a feed and build a Wordle visualization.

Merges state and local CAP/XML and RSS feeds to provide full-text, date-specific RSS feeds. Filtering by keyword lets you limit results to city, county, or conditions. NOTE: An empty feed means there are no alerts issued in your state with that filter. You can still subscribe to it for future…

Aggregates feeds in an OPML file into a master pipe, where all items from RSS or Atom feeds are sorted correctly by date. This is accomplished by creating canonical date attributes using Rename and Regex.