Ignore this, it is just a braindump from the train.  Unless you want to help out.

I’ve started working on a project called add-art.   The idea is to turn advertisements into beauty.  It is based on the popular ad-block-plus firefox extension, but instead of leaving holes where advertisements are removed, it would insert art.  Curators could book shows on add-art.org for artists.  When you go to a website with tons of ads, they would be replaced by art images.

Great stuff!   Once we get the plugin working with add-art.org, we should look at decentralizing it.  Let the extension communicate with multiple ad block lists and multiple replacement image servers.  Then package the add-art.org server as an installable package so anyone can run it.  Let users pick up the url of other servers as a way to get art from the artists they like on their browser…

Deviantart might run something like this.
Maybe flickr/explore/interesting could be a provider.
Hell, why not use atom/rss as the provider and let any rss list of images be the provider?
Image sizing becomes an issue.  You need to stick in appropriate sized images.  If they aren’t the right size you’ll need to slice them up on the client side.  Is that cheap?  Does the browser give you a way to not only decently resize, but also slice from an image?