Sam Savage has put another brick in the wall with Distribution Processing and the Arithmetic of Uncertainty, an article in the ORMS Analytics Magazine (2012 Nov-Dec).
The article expands on the concept of SIPs (Stochastic Information Packets) as packaged uncertainty. It shows how to use SIP math and raw Excel to do Monte Carlo Simulation "without the Monte Carlo."
He also introduces SIPmath – an Excel add-in to simplify building models that use SIP math. Once the model is built the add-in is no longer needed and the simulation can run without it.
Probability Management is on a roll. Read the article and then go to sipmath.com to learn more.