Dear Forum,
Perhaps you are aware about Mybloglog has been acquired by Yahoo. In your Mybloglog profile, you can provide links to your site as well as blogs. In addition, Mybloglog provides a widget that shows you the Mybloglog users that visited your blog or site. The common type of widget look like the image below:

The widget is composed of thumbnails and links to the profile of Mybloglog users. So, each time you visit a blog or site installed with Mybloglog widget, you get a link to your Mybloglog profile.
The code for this widget is composed of Java script, e.g.
HTML Code:
<script type='text/javascript' src='http://track3.mybloglog.com/js/jsserv.php?mblID=############'></script>
I am not sure if Google recognize the links to your Mybloglog profile from this script, but Yahoo does. However, this could be a potential strategy for building links.
But, the major problem for this type of link building is that, they are temporary links. The more the Pagerank, the more the traffic, and the links from high page rank sites are also more temporary. So, getting most from this link building strategy, you have to visit low traffic sites with low page rank. And build low profile links.
I am willing to know if anyone have tried this strategy and was it worth it?