Browsera is an all-in-one, web-based tool for testing web sites for errors, complications, and layout issues. Unlike other similar tools, it does more than just take screenshots of various browsers; it provides an in-depth assessment of problematic areas in need of attention.
Browsera is a program that has features similar to previously mentioned browser comparison sites like BrowserShots and IETester. Browsera kicks things up a notch, not only showing you what your site will look like to users with assorted browsers, but identifying and flagging problematic areas, making less dirty work for you.
Browsera is free with registration for use on up to 25 pages per month, which should be plenty for your weekend tinkering. If you need more, the service offers additional tiered pricing levels ranging from $49 a month to $499 a month as users and page views increase. The service currently runs its tests against the following browsers:
Windows: Firefox 220.127.116.11, 3.0.12, 3.5.0; Internet Explorer 6.0.3790.3959, 7.0.5730.13, 8.0.6001.18702; Mac: Safari 3.2.1 (5525.27.1), 4.0.3 (5531.9)