I buy online extensively, both at work and at home. I spend about $50 annually at home to keep my antivirus systems up to date. I am very picky about which e-mails I open and which remove from the computer immediately. I open those that I expect. I do not trust those that are unsolicited, even if from someone with whome I do business. If someone mails an attached and forwarded joke list, they are immediately deleated from my list.