eXorithm is a repository of algorithms that anyone can edit. It is also an execution environment, meaning any of the algorithms on the site can be executed on the server, with the results displayed on a page.
AKTIV built the website using PHP, CodeIgniter and MySQL. Allowing user-submitted code to run on the server presented significant challenges. Most importantly, all algorithms need to be checked for malicious code that could be used to compromise the server. Sophisticated parsers and validators were designed for this reason.
There is also a tool to embed eXorithm's algorithms on any other website. The algorithm still runs on eXorithm, but the results are displayed on the other website. Here's an embedded algorithm that graphs a function. Press the arrow icon to run it.