Joining the office Powerball pool isn't always a smart gamble. Pooling resources with a few co-workers can be an enticing prospect, especially now that the jackpot has ballooned to $700 million. The drawing is Wednesday at 10:59 p.m. EDT. Generally, it's better to buy your own tickets, said "Lottery Lawyer" Jason Kurland, a partner with Certilman Balin Adler & Hyman in East Meadow, New York. "I strongly dislike Powerball office lottery pools," he told CNBC. The Multi-State Lottery Association puts the chance of walking away with the grand prize at 1 in 292.2 million for a single ticket (see infographic below), and buying a few more doesn't move the needle much. "If you're going to take those crazy odds, you're better off doing it on your own so you don't have to split it," Kurland said.

If playing Powerball in an office pool, make sure photocopies are made, signed and distributed. Adam Jeffery | CNBC

With winner pools, the process of claiming and splitting the money can get complicated. For starters, it's harder to do what experts advise in big lottery wins: Stay anonymous while you figure out a plan for the money. Ideally, you'd have time to hire experts, like a lawyer, financial advisor and accountant, to figure out the best way to claim and manage that jackpot before the media crush brings attention and outstretched hands to your doorstep. But sharing the prize means more people know at the outset. Someone is likely to spill the beans. It could take longer to get your money, too, with each participant consulting his or her own team of experts. "The last thing you want is 20 lawyers involved in anything," said Kurland. Some states have limitations on how many checks can be cut, meaning a larger group could need to settle on a more complex solution, like forming a trust.

If you're going to take those crazy odds, you're better off doing it on your own so you don't have to split it. Jason Kurland The Lottery Lawyer

Then there are the tax consequences. Taxes on lottery winnings can vary by where you live and where you bought the ticket, so commuters who live in one state and work in another could lose a bigger percentage of their winnings to taxes. If one person or a few from a large group claim the prize on behalf of everyone, they take on the full income-tax burden. Money shared after claiming the prize would be considered a gift, said Melissa Labant, director of tax advocacy for the American Institute of Certified Public Accountants. With a prize this large, the gift giver is likely to incur gift tax, and have estate tax consequences. Despite those downsides, handing over a few bucks for the office Powerball pool is cheap peace of mind. After all, who wants to be the only person at the office on Thursday while co-workers are out rolling around in piles of money?