I found this page describing a number of algorithms for computing the factorial. Unfortunately, the explanations are terse and I don't feel like sifting through line after line of source code to understand the basic principles behind the algorithms.
Can anybody point me to more detailed descriptions of these (or other fast) algorithms for computing the factorial?
Edit: This page describes the method of prime factorization, the technique common to all of the best-performing factorial algorithms. It also contains some nice example code in Python. The author links to a description of binary splitting and references an article in the Journal of Algorithms ("On the Complexity of Calculating Factorials") that looks promising, if I could only get my hands on it.