How do you save for an apocalypse?

Many people believe the world as we know it will end Dec. 21, 2012. Many more don't.

And predictably perhaps, the idea has spawned a slew of books, movies and other enterprises keyed to the event. There are even T-shirts designed for the occasion. I haven't seen any word yet on what might happen to Christmas shopping.

The potential end of the world makes for some interesting financial planning questions too. Planners conservatively try to help us stretch our money into our age 90s or older. But if we only need to hold out three more years, the calculations are different. About two out of three households don't have a financial plan, Financial-planning.com reported recently. It would be ironic if they don't need one.

Seven in 10 Americans worry they don't have enough money saved for retirement, Bankrate.com found in one of its surveys. And thanks to the near apocalypse that hit our savings these last two years, more of us are getting serious about saving.

After all, 2012 may turn out as normal as Y2k. And FEMA will be on it.