What you need to know on Wall Street today

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If you're a fan of the corporate mega-mergers that keep getting announced, there's a good chance you're going to love 2018. At least that's the wisdom being touted by banks across Wall Street.

Elsewhere in deal news:

• Disney is about to go to war with Netflix and Fox could be a big weapon
• The CEO of Aetna is going to make a huge amount of money if the $69 billion deal with CVS closes
• Warren Buffett's Berkshire Hathaway rakes in $295 million from UnitedHealthcare's deal with Davita
• There's growing speculation Tesla and SpaceX could merge - here's why a deal would make sense
• Walgreens is taking a 40% stake in a Chinese pharmacy chain
• Home Depot is buying back $15 billion of stock
• China's Xiaomi is seeking a bank to launch what would be the world's largest technology IPO

In markets news, it's easier than ever to bet on the death of brick-and-mortar retail.

And in crypto news, traders on a $1 billion cryptocurrency exchange say they can't withdraw money and are left in the dark about why. Goldman Sachs asked clients about bitcoin's price trajectory. And one VC firm is starting a new blockchain fund - and plans to fund it with an initial coin offering.

Lastly, an 18-year-old is raffling off his uncle's £130,000 Porsche Panamera Turbo for £35 a ticket.