FINRA's 401(k) and IRA Minimum Required Distribution Calculator
The law requires that you begin to withdraw money from IRAs by a certain age. FINRA's MRD calculator allows you to find what your required withdrawal will be and the rate of return you'll need to earn to maintain your account balance.
FINRA's Smart 401(k) Investing
The Financial Industry Regulatory Authority (FINRA) is the largest non-governmental regulator for all securities firms doing business in the United States. This link walks you through the process of investing in a 401(k).
Social Security Online
Benefits information and more from the Social Security Administration's web site.