I can’t remember where I saw this now, but it’s pretty cool. MyScript Calculator is a calculator that takes handwriting instead of using buttons. But what’s really cool is that if you put a question mark into part of the calculation, it will solve that for you.

For example, I often bake things that require a specifically sized square pan, and I don’t have that pan. But I’m guessing that my round pie tin will come pretty close.

So I scrawl this—and it really is a scrawl—putting a question mark where the diameter of the circle goes:

And then, MyScript Calculator converts it successfully to an equation and solves for the question mark:

So if I use a 9-inch diameter pan, it should be pretty close to an 8 by 8 pan.

The calculator is less useful on the iPhone because there just isn’t room to scrawl, but it works great on the iPad. It’s like living in the future.