Cool stuff: Here's how to build your own Yahoo Pipe

Computerworld - Want an easy way to find an apartment near a specific location, or track items on eBay in a certain price range, or see all the news that interests you in one place?

Yahoo's new Pipes service may be for you.

Still in the early stages of beta, the "interactive feed aggregator and manipulator" lets ordinary people -- even Computerworld editors -- customize RSS feeds and build mashups from different sources.

It was so popular upon first being introduced Feb. 7 that it crashed Yahoo's servers the next day. Visitors were greeted with the message: "Our Pipes are clogged! We've called the plumbers!"

After a good flushing, the service has thrived, with thousands of new Pipes being built, discussed, shared and improved among an active user community.

Using a simple drag-and-drop system, users choose modules and drag them to an editor where they are configured and connected through flexible, winding ... well, Pipes.

So, for instance, you can drag out a "Fetch" module that simply includes a text input box where you specify the URL of an RSS feed that you want to use. Doing this automatically creates a "Pipe Output" module. You can click on a button on the bottom of the Fetch module that generates a flexible Pipe that follows your cursor. Connect the Pipe to the Output module and you have an instant application in just a few minutes. You can then "publish" the Pipe so it is accessible by others or keep it for your own use at a specific URL or as an RSS feed, for instance.

While that is the simplest example and not very useful, it's easy to add more feeds, customize their presentation and combine information from disparate sources into one application. Some of the more interesting Pipes have been built using modules for user input, operator functions such as sort and count, date formatting, and built-in sources such as Flickr and Google Base and, of course, Yahoo search.

For example, one Pipe called "Apartment Near Something" combines Craigslist and Yahoo Local to generate "searches for apartments near things you care about!"

Another one called "New York Times thru Flickr" takes The New York Times home page feed, passes it through a Content Analysis module that extracts keywords to find related photos at the Flickr site.

One called "eBay Price Watch" is described as "designed to use eBay's RSS API to find items within a certain price range."

Yahoo says it's seeking user input to improve the service, and that plans already in place for future versions include:

• Programmatic access to the Pipes engine
  
• Support for additional data sources (such as Keyhole Markup Language)
  
• More built-in processing modules
  
• The ability to extend Pipes with external, user-contributed modules
  
• More ways to render output (Badges, Maps)