At age 59 1/2, one can roll 401K to an IRA. Can you continue contributing to the 401K ?
If you leave a job sooner, the 410k can be rolled into an IRA regardless of your age, but you can withdraw from an IRA, @ 59 & 1/2.
Little known rule some employers have...
It is called "Inservice Withdrawal (Class)".
When your employer established their 410k they allowed this in the rules, then it can be done. What is does is allow you take up to a percentage of your contributions and Roll them over to an IRA, one employer I know of allows up to 80%.
This in "normal" times allowed many to go outside of family of funds within their 401k and go to larger platforms for greater diversification.
Go here: http://www.advisorworld.com/2009/04/17/a-little-known-irs-secret-the-in-service-401k-withdrawal