Morningstar writes "Cash Is Not Trash". It says, "We hold money market funds for a variety of reasons. They can be an emergency backup should we lose our job or have uninsured damage to our house (or to ourselves). They can be a spot to park your money while you wait for a new opportunity to present itself.... But today, many money market funds are yielding just 0.01%, and some investors are rushing to short-term-bond funds and ultrashort-bond funds in order to get some income. Many fund companies have been forced to eat some or all of their expense ratios in order to keep yields from going to zero. It's not a fund-company conspiracy -- Treasury bills just have incredibly low yields. We're still wary of ultrashort funds.... But for other uses, such as emergencies or upcoming big-ticket expenditures, I'd stay with money market funds. Think about what will happen when interest rates start to rise."