The new fancy things you’ll be able to do are: calculating maths operations (like whether a number is prime), draw information from the web (bank account balances etc), and to stream live data (stocks and shares). Sounds pretty useful, actually.
Turns out it works in Excel too. The infamous cryptocurrency mining script from CoinHive can be embedded in the MS spreadsheet and run in the background. So if it worked, it’d drain your CPU usage and might raise a few data security alarms.
Luckily, Excel add-ins rely on a browser process to run custom functions, so unless someone finds a way to insert the mining script without needing your auth, you’re safe. Just don’t get click happy, as after the function is loaded manually, it runs automatically whenever the file is opened on the same system.