Hi, I'm not retired yet, but I know there is something called the 72(t) section of the IRC, the exception to the 10% penalty tax for withdrawals from IRA accounts taken prior to the age of 59.5.
I believe you'll have to rollover your 401(k) funds to an IRA account and then take early distributions based on the guidelines of 72(t), and you won't be paying penalties.
Here's a website dedicated to it:
Click the "72t Early Distributions".
I'm sure the retired folks here will give you more info on this.