A couple years ago, I used Node.js to build a tool that would run tests in iframes. It's similar to the OP's tool Thrill, but mine was a lot simpler. http://thr

A couple years ago, I used Node.js to build a tool that would run tests in iframes. It's similar to the OP's tool Thrill, but mine was a lot simpler. http://thrilljs.com http://thrilljs.com The problem we (the YUI project) ran into was test failures that would occur only within iframes. We found lots of iframe-only quirks that were useful to know about, but were also distracting since we wanted to make sure using YUI in a typical browser context works first. (I've talked to jQuery's TestSwarm maintainer and they've had similar problems with iframes.) The tool we use, Yeti, was since rewritten to not require an iframe. http://yeti.cx http://yeti.cx I continue to work on Yeti, and there's a lot of interesting things we have done (using multiple browser instances to speed up testing, launching browsers automatically, CI integration) and hope to do (code coverage, performance measurements). Help wanted! It's neat to see this kind of thing become more popular, and I hope these projects can make testing easier for everyone.