Price comparing engines can bring additional traffic to your site. The ROI is farily good seeing that the integration can be done with very little effort.
Here are samples of how to integrate with the main italian product comparison sites:
Prezzistop
category1::category2::category3|Brand|ProductName|description|image_link|price|deeplink
Kelkoo
http://support.kelkoo.com/it/pages.php?page=174
Trovaprezzi
Fisio 330|Philips|Cellulare Dual Band configurazione Wap|140,20|A1234|http://www.sito.com/vai.asp?id=A1234|Disponibile|Cellulari|http://www.sito.com/images/image1213.jpg|10,00|CT3308<endrecord>
Pen Drives 2GB|Transcend|Pen Drive Professional 2GB USB 2.0|8,60|TS2GJFV20|http://www.sito.com/product.asp?Id=219|Disponibile|Informatica, Chiavette Usb/Pen Drives|http://www.sito.com/images/219.jpg|9,99|TS2GJFV20<endrecord>
