Making a web application mashable -- useable in another web page -- has some challenges in the area of cross-domain communications. Here is how I solved those problems for Zwibbler.com, using HTML5 cross domain communication.
How do you measure the "sortedness" of a list? There are several ways. In the literature this measure is called the "distance to monotonicity" or the "measure of disorder" depending on who you read. Here, I propose another measure for sortedness.