browserling - Live interactive cross-browser testing from your browser.
One Click Test - Tool for quickly testing your design layout in one click.
Sauce Labs - Test mobile or web apps instantly across 700+ browser/OS/device platform combinations - without infrastructure setup.
XPRS - Free website builder - making web design like Lego™. No code
Browsershots - Browsershots makes screenshots of your web design in different browsers.
Dimensions Toolkit - Chrome Extension for designers to test responsive websites.