Interesting firm that I came across a few months ago. They have built a platform that screens a universe of around 40,000 equities and filters them according to the Sharia criteria that you input to give you an investible universe of equities.
During a demo that I was given last Thursday, I found that they also have the ability to calculate income purification as well as allowing you to track equities over time for ongoing Sharia compliance.
More information about the firm can be found at www.idealratings.com.