Mean Variance Optimization (MVO) and Monte Carlo simulations
The existing options range from VisualMVO (http://www.effisols.com/visualmvo/index.htm) to G-Sphere (http://www.gravityinvestments.com/). VisualMVO costs about 90$, but you have to enter *everything* in by hand. G-Sphere costs $3500 per year (!) and pulls data from a server, but you still have to enter your portfolios manually. Zephyr makes a product that costs $5000 per year.
I would be willing to pay extra hundreds$ to see even the more limited functionality of VisualMVO in Fund Manager, since it does everything else so well. I suspect many others would too.
cheers, jens