From the Powerball FAQ page, about 2/3 down the page:
HOW LONG DOES IT TAKE TO GET MY MONEY?
It takes up to two weeks to collect the cash from the stores around the nation. If you go to the lottery to claim your prize after that two weeks, then, in many states, you can generally have the jackpot money (all cash or the first of the annual payments) hit your bank account the next day - maybe the following day if you come to the lottery office very late in the day. Some lotteries must work through the state system and that can delay the payment. That said, Powerball jackpot winners genneraly don't have trouble getting a little credit if you wish to buy something before the money arrives. Just mention my name - and that you are the Powerball winner.
I always thought that last part was funny, plus the spelling of "generally". (I don't care HOW they spell things, just as long as they get the numbers right!) Yep, if you showed your banker your winning lottery ticket and he verified it by some reliable source (although I wouldn't let him hold the ticket, just look at it to make sure it was legit), he'd probably loan you some money. If he didn't, then I'd look for another bank to send the wire transfer to when I claimed.
(Although I'm sure he would loan you some money, esp. if you told him you'd buy a CD at his bank with your winnings after it got there. Just don't let him know it's not going to be a $250 million one but a $250,000 - or less - one)
Here in Texas, you have to opt for either the annuity or the C/V on the play slip. The machine won't take it otherwise, at least that's been my experience when I've forgotten to shade the appropriate box. I try to bring my Texas Lottery provided "wallet" with previously filled out slips with me, but if I haven't brought it with me and just ask for a quick pick, I tell the clerk I want the multiplier and cash option, but now it's automatically cash option unless the clerk inputs the annuity selection for you. Vending machines also have cash option as the default, too and the one I sometimes use has no way to opt for the annuity unless you use a play slip. I'm not positive, but I'm fairly sure that it's a locked in choice from purchase to claiming. No problem for me, I always go for lump sum.