InstaCalc is an online calculator that can be embedded in a web page, edited by anyone, displayed in charts and shared in a given state with a link. If you’ve got a formula and some numbers, you can post it on your blog or website and I can see how things would work out with different numbers. The math is done in real time.
As you can see below in developer Kalid Azad’s example based on Fred Wilson’s YouTube valuation math, any of the fields are editable including the notes field. Once you make changes, you can save and share your version with the link in the top right. Update: After about 12 valiant hours of surviving TC and other traffic, it looks like Instacalc is having a hard time with the load of being embedded. I’ve removed it from this entry but you can go here to see Instacalc in action.
InstaCalc was created by former Microsoft employee turned entrepreneur Kalid Azad. The system recognizes some limited natural language and if you click on the save link you can view a full page with graphs and charts. It’s a lot of fun to use once you figure it out, but the interface is a little complicated at first. It just launched, so it doesn’t work perfectly either. The embed code, for example, didn’t work for me out of the box. InstaCalc is obviously only capable of so much, but it is a fast, loose way to share numbers and formulas in a blog post or other site. It’s really quite remarkable, I think.
If you’re looking for something similar but more heavy duty, Dan Bricklin released his newest version of WikiCalc yesterday and it now supports all 109 functions listed on the standards site OpenFormula.org.