I used to have this problem as well, we regularly would amass 20k or more in a low interest savings account. My solution was to invest more into our PG account through computershare DRIP, which does not have fees. The stock also pays dividends. This is not a risky stock because it's a consumer stock, and as such, does not decline as much in market downturns as other stocks do. We are now down, after convincing my wife for many years, to 6k in savings. However, we have amassed 64k in our PG investment account. It's taxable, but you only pay capital gains when you sell, and the dividends are small and taxed at 0% if you are in the 15% federal tax bracket.
We also recently opened up a sharebuilder account, and invested 7k in AAPL stock. This also pays a nice dividend. My advice would be not to live in fear, and sell your stocks if you should lose your job and run out of all other sources first, such as:
1. savings
2. severance pay
3. unemployment benefits