A few years ago, my identity was dopplegangered and used to purchase almost $10,000 worth of goods, none of which I ever saw personally. Unfortunately, this happened twice, once with each of two separate credit cards. Since then, I’ve made a conscious effort to protect myself… these are some of the steps I’ve taken:

• All mail that might even hint if personal information is shredded. This includes credit card offers, everything in bill envelopes I don’t use to pay the bills, any notices from any organization that includes any personal information… pretty much everything but magazines I keep and advertisements. If you don’t have access to a shredder, I cannot over-emphasize the value of getting one. They’re not that expensive.
• On the back of credit cards, instead of my signature, I write “Photo ID Required”. If they don’t take that as legitimate, they don’t have my business.
• I have set passwords with all credit cards possible, so that I have to give them the password when I call. Unfortunately, they typically err in favor of helping, me rather than denying me on those occasions I’ve “forgotten” my password.
  On any receipt that contains the full CC number, I obscure all but the last four numbers out… seriously, who still prints the full number?
• Whenever asked for my SSN, I ask for an explanation on how it’s being used. If it can’t be explained, I politely refrain from providing it until it can be. The same goes for phone numbers and drivers license numbers as well. One can’t be too careful.
• Whenever providing any personal information online, I make absolutely sure that the delivery method is encrypted and secure (HTTPS, SSH Tunneling, etc.). This helps guard against possible man-in-the-middle attacks.
• I don’t click on links in e’mails. Ever. If I must follow a link in an e’mail, I copy/paste it into a browser after verifying as much as possible it’s legitimacy. This helps guard against phishing attacks.
• I don’t open attachments in e’mail unless they are from trusted sources. Period. Even then, if I have any doubts, I will confirm it via phone call or separat e’mail. This is generally not a problem since I don’t check my e’mail on a Windows based system. This helps prevent my computer from becoming a member of a bot-net.
• Receive quarterly credit reports and review them for nefarious activity, or just activity I can’t explain.

Does anyone else have any other tips?