It's mega madness -- again.

A $400-million jackpot is up for grabs Friday night in the Mega Millions lottery game.

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Customers bought about $1,000 in tickets Wednesday and Thursday at Cards N Things in Holbrook, well above the usual $200, clerk Piyush Patel said.

"They say, 'A dollar and a dream,' " he said with a chuckle. "They know they're not going to win."

Still, he said, he has $8 in the Mega Millions pool at his other job as an electrical technician.

The cash option is $216 million, according to the Mega Millions website. The game's biggest-ever jackpot, $656 million, was won in 2012 by three people.