Are there any keywords I can use in a search engine like Google, to look for ATG web sites.
For instance, for IBM's WebSphere Commerce, you can key in "wcs/stores" and you will get a list of web sites running on WCS.
The reason for getting these results is some of the links of these websites are having wcs/store in the url. As Google's Page rank algorithm for search results ranking gives more weightage to the url, these links are appearing as the results for the search term 'wcs/stores'. We do not have anything similar to this in case of ATG.
Also, I feel that this might be an vulnerability to expose what technology is used in a website, as the site could be tested by hackers for known exploitations of that technology (However other ways to find the technology used might exist)