I often see Picasa images embedded in forum messages, but I sometimes would like to access to the albums they come from.
Flicker allows this kind of request using their API, flickr.photos.getInfo. You enter the CDN filename from the image link (http://farmnumber.staticflickr.com/server/photo_id.jpg) as the photo_id, and browse the information related.
Do you people know a way to achieve the same thing with Picasa?