That's a pretty neat idea to use simulation as part of financial planning. I know I've seen general projections of retirement money, but using the simulation as an interactive tool to help tailor the plan makes it seem much more personalized and useful (though who knows if that is actually the case).

I'm not sure how successful this could be targeted at individuals without being integrated with some other financial product like a retirement account provider, though. It would certainly be nice to have something like Mint for retirement to consolidate and track overall allocations over many accounts from different providers.