Few everyday offerings fall into the realm of free. E-mail accounts still make that list. But as with any freebie, there are associated costs. One of the most substantial stigmas attached to virtual mailboxes is spam e-mail. Within one folder of utter clutter exists unsolicited messages delivered to thousands of addresses. Those not smart enough to read the warning signs might befriend the fictitious Alan Lutz of twistedtails.com, offering a chance at a low mortgage rate "Because you deserve it!" Without the right protective programs in place, that decision may drastically affect the average computer's shelf life. And for those who are wise enough to ignore the jungle of junk, the process adds Web traffic to only one obsequious computer key — the delete button.