11 Ways To Tap Retirement Cash Early

Two important reminders in this slideshow from Forbes:

... You can take a distribution from an IRA or 401(k) penalty-free to pay for certain medical expenses. Be careful: Beginning in 2013, only expenses that exceed 10% of your adjusted gross income are eligible, and you must pay those expenses in the same year you take the distribution.   

... If you're unemployed, you can take money penalty-free--from an IRA but not a 401(k)--to pay for health insurance. To qualify, you must be on unemployment insurance for at least 12 weeks, and you can't take the money out more than 60 days after getting a new job.

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Of course, while the two methods above are penalty-free, they are not tax-free.  You would still have to claim the money as income.