Most of us have a basic understanding of products like CDs, money markets, high-interest savings and other kinds of low-volatility accounts. Keeping in mind that a credit union can often provide better rates and interest on accounts of this type, consider this: Retirement is what IRAs and 401(k)'s were invented for, so you should already be contributing to one or more of those before looking further.
That's the long view, as with life insurance, and it's important, considering none of us really knows our future earning potential. Your emergency fund should be accessible -- it's for emergencies, after all! -- and there shouldn't be a lot of penalties associated. The price you pay for accessibility, of course, is interest rate.
But for money that's not immediately necessary, but neither extraneous enough that it can go into your retirement fund (or, if you're really doing it right, what's left over after you've maxed out your contributions for the year), you need a middle option. That's when a portfolio or brokerage account -- if you're feeling lucky -- or a CD ladder -- if you're feeling prudent -- comes in handy.
Simply put, by engaging in a high-yield, short-term CD for the maximum amount, you can control your own compound by reinvesting at the end of each term period for a given term that you specify, meaning that if investing in a 10-year CD stresses you out this year (most CDs incur penalties if you withdraw your money early), you can take a 5-year option and see where you are when it matures. It's not instant access, but it's comforting in the middle-term.