If you were to convert this html content into a small thumbnail image , how would you do it?
P.S. I'm trying to do this to allow users on my site to browse through their posts(containing html elements (e.g. strong, i, img tag's).
They have a pretty decent simple API
Simple syntax to use the API: http://api.thumbalizr.com/?url=http://www.ford.de&width=250
Check http://api.thumbalizr.com for more details.
So you can simply have
<img src='http://api.thumbalizr.com/?url=http://www.yourdomain.com&width=250' />
Also see http://www.websnapr.com/ and their implementations page