CircuitLab is coming up on its one year anniversary, and the startup (now part of Y Combinator’s winter 2013 cohort) now boasts 70,000 monthly active users, who run an average of one circuit simulation every six seconds. The phenomenal traction for the electrical-engineering-focused startup has a lot to do with the team offering up a tool that’s both free and particularly well-suited to educational use, and it bodes well for CircuitLab’s chances of helping early stage hardware startups get off the ground.

The designs for all those wonderful Arduino and electronics projects don't create themselves, sadly. No, a person needs to put in time and effort laying out the circuits and carefully arranging the components, often by hand, but sometimes with aid of a software tool. A new player in that field is CircuitLab, a surprisingly full featured app for sketching out schematics and simulating them that lives entirely in the browser. It's also amazingly user friendly and simple for even the novice hobbyist to dive into. Finally, once you've finished with your project you can make the design public and share it with others.