You leave it in checking accounts or, if you are looking for interest/return, put it in an investment account. The movement between these accounts is pretty seamless at many banks these days. In my case, there are no fees associated with putting the money in investments so it makes it very cheap to put the money to work.

Savings accounts are essentially restricted checking accounts, so what's the point? The interest rates on both types are the same, at approximately zero (pennies of annual interest on a thousand dollars).