A Sig File (or Signature File) is your best stealth marketing device. At the bottom of every email you send or every message you post in a forum, add a few lines of key information about your company, product or service, and include your Web site's URL. Don't be blatant or take up too much space. A tasteful slogan with a link to your Web site will attract more visitors than an overly commercial pitch, which is likely to offend people. Most e-mail software programs have a Signature feature to automatically "stamp" the bottom of each e-mail you send. Or save your Sig File in a text document and copy and paste to the bottom of your messages whenever appropriate.