Ah, I remember the days of Intel's fabs doing “too good” a job and many more chips passing tests for faster use being produced than expected. To fulfil orders for the slower chips some of these better batches were marked down and sold as slower units, so if you were lucky you could really push the overclocking and get yourself a performance bargain. You also needed a good motherboard and quality RAM to pull it off reliably, of course.

Sillyrons is what we used to call the massively overclocked Celerons. At Uni a friend of mine made a good bit of pocket money from selling an optimisation service, for people who didn't feel confident playing with such settings themselves.