when you do RECIPOCAL linking from you homew page it singnals artificial network to increase PR.
This is why I am using this free link exchange manager, and I do agree when you have many sites and you need a link exchange solution you just can’t efford this extra cost, but link swapper is just one of the applications that I choose there are other free ones in the market, I just want to the one most of the webmaster I know were recomending
/Janet