AmazonScan.com is a program that scans different products on Amazon.com and records their sales ranking over time.
Theory of a Higher-Order Sturm-Liouville Equation (Lecture Notes in Mathematics (Springer-Verlag), 1659) isn't doing too well being ranked at 2,209,455th.
The Simpsons - The Complete First Season on the other hand is doing well at #4.
