The Google AdSense preview tool is an addition to the right-click menu for Windows Internet Explorer 6.x, allowing you to preview the ads that may show on any web page. With just a few clicks, you can see what ads may appear on your new web pages, or make an educated decision on whether to add AdSense to your existing site pages.
Other features include:
Check the destination of ads that are on your page: ads displayed in the preview tool are in a test state, so you don't have to worry about accidentally clicking on an ad. Clicks and impressions are not counted against the ads that display within the preview tool.
View sample ad formats and colors: create previews of formats and color combinations within the preview tool. Choose from 2 different preview formats, plus a 12 ad spread that allows you to view more available ads at once.
Preview colors on your page: the 'Preview' feature of the Color Options menu allows you to see what new color combinations would look like on existing AdSense standard ad units, right on the page. By simply selecting new border, background, or text colors from the preview tool, and clicking "Preview," the new colors will be temporarily applied to the standard ad unit currently on your page.
Geo-targeted locations: select the geo-targeted location from which to view ads, allowing you to see what users in Canada will see, even if you live in Japan.
AdSense providers aren't allowed to click on AdSense ads; this preview tool does get around that. Unfortunately it's IE only (yech). Google needs to get away from all these IE only solutions.