You can add thumbnails of webpages to your blog, without any picture software!
No, the thumbnails are generated and hosted by http://www.picdonkey.com
No, only use the tag [thumb]YOUR_URL[/thumb]
If you want to style your thumbnails you just have to use the css class picdonkey.
height: 200 and width: 150
Yes the link on the thumbnail opens in a new window with target _blank




