What are some alternatives?
CutyCapt - CutyCapt is a small cross-platform command-line utility to capture WebKit's rendering of a web...
BrowserStack - Test your website for cross browser compatibility on real browsers. Instant access to multiple desktop and mobile browsers. Get Free Trial.
Browsershots - Browsershots makes screenshots of your web design in different browsers.
Sauce Labs - Test mobile or web apps instantly across 700+ browser/OS/device platform combinations - without infrastructure setup.
browserling - Live interactive cross-browser testing from your browser.
IETester - ietester is an application that allows to test on multiple ie versions at the same time in the same application