A client that I picked up a couple of years ago was into some heavy reciprocal linking. In his industry, he was always getting hit up with reciprocal link requests.
I advised him that most of these requests were scams and the link pages were probably blocked from search engine spiders, did not pass PageRank or the links used the nofollow attribute. He didn't believe me, but followed my advice and checked out his link partners. Out of 42 link exchanges, only two were legitimate. He was pissed!
"Democracy is two wolves and a lamb voting on what to have for lunch. Liberty is a well-armed lamb contesting the vote." -- Benjamin Franklin