Amanda Terkel at Huffington Post introduced this bit of conjecture into the already ridiculous Republican presidential candidates race, and it is has now happily gone mainstream with all the other foolishness associated with the Republican field this year.

Rachel Maddow had a bit of fun last night exploring this topic at Herman Cain's expense.

In Herman Cain's America, the tax code would be very, very simple: The corporate income tax rate would be 9 percent, the personal income tax rate would be 9 percent and the national sales tax rate would be 9 percent.

But there's already a 999 plan out there, in a land called SimCity.

Long before Cain was running for president and getting attention for his 999 plan, the residents of SimCity 4 -- which was released in 2003 -- were living under a system where the default tax rate was 9 percent for commercial taxes, 9 percent for industrial taxes and 9 percent for residential taxes.

Cain denies any of that, calling such accusations blatant lies to discredit him, now that he's supposedly a front-runner for the nomination. Given Cain's strange history with pop culture references though it's quite believable, or at least as believable as anything else associated with his "campaign." I'm still not convinced that Herman Cain is not just a fictional candidate, running an extended book tour who now finds himself caught up in the moment, somewhat bizarrely leading the pack of oddballs otherwise known as the Republican candidates for president.

Herman Cain's campaign slogan: "A SIM-PLE PLAN FOR A SIMPLE MAN."