Given how low rates are, it's not worth the effort to do anything complicated with it. If you're not going to be accumulating any more, just keep it in your bank account for now.

If you are in a mode of accumulating savings, then I'd open up a vanguard account and start with either the money market fund or short term bond fund. As you save more money, you can allocate some of it to slightly riskier investments.

I like to roll mine into ibonds over time (partly because there is an annual limit, and partly because there is a one year min. holding period). Have some in an internet bank too.

I used to use a CD ladder before interest rates got so bad.

Some people put it in a short term bond fund, but those have more potential to lose some value (although the yield is probably better and they shouldn't be too volatile).

We have a 60k cash emergency fund. Should we keep it cash or invest in something conservative that we could sell quickly?