To try something little bit larger, I ran the Mersenne Prime search program described below on 100 nodes searching all the Mersenne primes with an exponent up to 25,000; the last one in this interval being 2^23209 -1 discovered in 1979 (less than 30 years ago!). The program ran for 12 hours, was simple to write (a simple Java program), and it was just a matter to upload it to the Grid, submit it, and dowload the result. While of course, it is difficult to compare with other searches, this page describes how the 32nd Mersenne Prime was found: a specialized program written for a Cray-2 supercomputer.