This is a great article/ piece about Follow and No Follow web links for SEO purposes.

Follow Links Vs. No Follow Links: Should You Care?

"A no follow link is a link that does not count as a point in the page’s favor, does not boost PageRank, and doesn’t help a page’s placement in the SERPs. No follow links get no love. Theirs is a sad and lonely life."

If you do not already have the MOZ toolbar for this purpose, I would suggest it.