That was the inspiration for this site a few years back. I wasn't a Mac user at the time so couldn't even try Soulver myself but thought it was a cool idea.

Soulver's WolframAlpha support is great, too. No need to switch to a browser to bring in some real world data.

How do you do this?

Settings > Calculator > Wolfram|Alpha. You provide a Wolfram ID from WolframAlpha and then "= ?" in a sheet will query WolframAlpha for the previous variable.

https://twitter.com/soulver/status/1592207142047698945