Our example looks for photos of the Chicago skyline. The Flickr module is set to return up to 200 images tagged with the words "chicago" and "skyline". We'll also ask for photos that are near Chicago, IL.
To further hedge our bets, we run these results through a Filter module. We only want those photos with a valid geo-location, so one filter rule blocks items with bad latitudes. A second rule eliminates any item with a title that doesn't include the word "Chicago".
Pipe Web Address: http://pipes.yahoo.com/pipes_team/aJgH8t5S3BGRQ8Rs2h2EvQ