I'm working on a site at the moment and a number of the links on the pages do not need to be followed by the search engine (or other) spiders and do not need to be indexed. These links I set with the nofollow value on the rel attribute in the anchor tag follows:
<a href="some-link-goes-here" rel="nofollow">link text</a>
Some of the pages have plenty of links and I'm never sure if I've marked all of them correctly but I would know if I could color the already marked ones. This is easily achieved with jQuery. I open up the page in FireFox and then open the Firebug Console panel and in there I type:
This will cause all of the links on the page with the rel attribute set to nofollow to be colored pink. You can then easily perform a visual check to see if you've caught them all.
(It will actually cause any text inside any tag with a rel attribute set to nofollow to be colored pink but I believe that the only recognized tag that rel is used with is the anchor tag.