During the 08 financial crisis, Mitsubishi wrote a $9 billion CHECK to close an investment in Morgan Stanley over a holiday weekend. The concern was that MS's stock would nosedive if the deal wasn't done before the market opened. The check was apparently enough to legally close the deal on a weekend when it wasn't possible to wire funds.

There's even a picture of the check on MS's Twitter: https://twitter.com/morganstanley/status/1315673245291614208...