Desmos is a new company that has created a fully functional, browser-based graphing calculator. The calculator performs all of the functions you would expect to see in a graphing calculator with a couple of extras that you don't find in typical graphing calculators. Desmos allows you to share your equations and graphs through a Bit.ly link. Desmos graphs your equations as you type them and redraws them as you alter your equations. Watch the video below to learn more about the Desmos calculator.
Read TechCrunch's post about Desmos to learn more about the company and some of their plans for the future.
Applications for Education
Desmos could be the replacement for those expensive TI calculators that sometimes disappear from schools. I like that you can share your work via shortened Bit.ly links. I could see teachers modeling with Desmos and sharing. I could also see students sharing to do collaborative problem solving. The one thing holding Desmos back is that it's Flash-based and not ready for the iPad yet.