I was wondering if anyone knows of any hosted solution that can take snapshots of given websites.

Basically I want to have automation scripts that navigate a certain pattern on the web. I need to compare the html we grab from these and parse them, and want to do it through automation. So for a given week, I want to take a snapshot of a group of websites, and run my automation on that so I can compare across different browsers/os platforms.

Is there such a solution available?