Mashups are all the rage these days. ProgrammableWeb.com is the comprehensive reference for all the mashups and APIs out there.

Two mashups recently caught my eye because they bridge the Desktop and the Web. (Most mashups are a combination of two websites.)

• Twaingle (Windows only) is a Flickr powered TWAIN driver. TWAIN drivers connect your computer to a scanner. With Twaingle installed, the “scanner” is Flickr. You can go into Photoshop or some other graphics program, choose “Acquire image” as if you were going to scan something, then search for a photo on Flickr! Very ingenious!
• Pyro (Mac only) is a web browser built specifically for the Campfire chat application from 37signals. Campfire is a great chat application, but because it’s browser-based, it can’t, for example, cause your browser icon to bounce when you receive a new chat message. Pyro solves this by integrating the web-based features of Campfire with the desktop features of Mac OS X.

These are a whole other type of mashup. Expect to see more like them.