Straight-forward answer.
Roth IRA. Contribute for 2013 and 2014 from Troweprice, Fidelity or Vanguard
Take Care
The answer to that is that until you put background with it, there is no good answer.
Questions like,
Is this money you can afford to lose, or all that you have?
What do you expect from the investment- no risk? fast gains?
If you don't apply your parameters and limits to the idea, you give away all your control and you might as well go to the casino with it. If you don't know how to invest on your own, then find a financial adviser with a very good reputation and record, and let them help. In the alternative if you have a relative with a strong market track record, ask them for help.
Until you have a plan with a good foundation, Samdude's answer makes sense- sit on it until you do your homework. It won't grow in the bank, but it won't go down the drain either.
Depends on your age. Younger riskier bets, older safer, nearing retirement out of the market and into bonds cds or safest investments. Be aware that IRAs will lock up your money in return for the tax advantage they provide. If you're in the 10% bracket and are likely to stay there, they may not be the best ideal.
In your bank. It is called having an emergency fund.
Straight-forward question.