It's great to have a 401(k), but not everyone knows that you don't have to wait until you're old before they become useful. There are a number of reasons you can take cash from your retirement account. It's basically taking out a loan from yourself. Funds from 401(k)s can be used to pay for a myriad of things, from medical expenses to financing a business to buying a home--although there should be a smart reason to take a loan. No vacations or big-screen TVs.