SimilarSites.Net is now using thumbshots.org which is a free service to get web page thumbnail images. They have a nice effeciant service and mostly thumbnails are available for any provided url. In similarsies.net we are using it mainly on the list of similar websites page so that users can get a quick preview of each website in the list.

This is a great service if you want to see some more similar services you can check this out.

http://www.similarsites.net/Site-thumbshots.org.aspx