Sauce Labs
saucelabs.com
saucelabs.com
I am surprised things like this arent more popular, although I doubt I will ever do unit testing as a service, Im pretty interested in seeing what they come up with.
You need our service to make sure your web apps work in all the popular browsers.
We've got a bunch of web browsers in the cloud which you can remote-control via and API, to make sure the features of your site work cross-browser. We use a popular open source browser automation tool called Selenium, which my cofounder Jason Huggins created.
I'm curious whether the above description makes sense, or still leaves you scratching your head!
During our beta, we'll let you try sauce's service for free if you ask nicely (and answer a few questions).