Unless you're still living in the technological dark ages with 8 track tapes, you know that your computer must have anti-virus software on it to keep it safe from viruses. These viruses have become so sophisticated that they can find your bank information and take money right out of your bank account. (For related reading, also take a look at 5 New Phishing Scams To Watch Out For.)

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The rotary phone is dead and the land line will probably suffer the same fate in the near future. What has taken their place are "smartphones" that can do everything a computer can. Most of us, though, haven't thought of the downside to the rapidly evolving cell phone: the more it can do, the more vulnerable it is to cyber attacks - the same cyber attacks that have caused great financial loss for unknowing consumers all over the world.

Let's take a look at a few ways that your smartphone could end up costing you more money than your already expensive cell service bill.

1. Denial of Service Attack
Let's translate this techy argument in to every day terms. Have you ever gone to a party with a close friend or loved one and once you got there, you ended up with so many people wanting to talk to you that you couldn't get away to talk to that person who was more important than all of the others? That's what a denial of service attack is.

Here's how it works: You may have been surfing the net on your phone and clicked on a site in a bad section of cybertown. It installed a piece of software on your phone that allowed somebody to gain access to your bank account records that were stored on your phone. Then, the criminal, using an automated system, sent you a series of phone calls that tied up your cellphone so no calls could go in or out. Then, the criminal went online and used your information to make a big withdrawal from your bank account. When the bank calls you, they can't get through. A few minutes later the criminal calls the bank posing as you and verifies the transaction. Some people have reported losing their entire retirement savings as a result of attacks like this.

HOW TO AVOID IT: Don't leave financial information saved on your cell phone and don't post anything remotely personal on social networking sites.

2. Install Antivirus Software for Your Phone?
Sounds like a good idea, doesn't it? In reality, you don't need it (yet) and because of that, there are very few companies who offer it. What's worse is that a mobile virus is infecting people's phones all over the world, posing as antivirus software for your phone. If you install it, you're going to receive a whole host of spam messages on your phone each day. Doesn't sound like much more than a small annoyance does it? Wrong! Users who downloaded this virus had an estimated total of $300,000 in text message charges PER DAY! That's a lot of messages and the time you're going to spend trying to sort this out with your cell phone carrier could cost you in vacation days and sick time.

If that isn't enough, it also finds the numbers of all of your contacts and spams them as well.

HOW TO AVOID IT: If you receive an offer for free anti-virus software, don't click on the link. If it's from a company that you believe you can trust, go to your cell phone's app store and download it directly from them.

3. Third Party Premium Services
The only premium part of these services is the premium amount of headache they cause. Have you ever taken an IQ test, online poll or some other seemingly harmless service like dialing a number for your horoscope using your cell phone? That "who is the best dressed celebrity" poll you took yesterday may have signed you up for a monthly service costing somewhere about $10 per month.

You may have never authorized it or you immediately canceled the service but often, canceling these services is a major headache because the owner of the service is banking on you paying the fee rather than putting the time in to fight it. Because these services can be difficult to cancel, they can end up costing you hundreds of dollars if you have to get a new phone number and new account.

HOW TO AVOID IT: Stay away from the free, fun quizzes and polls. If you're inclined to do these types of activities, do them on your computer where they aren't tied to your phone and you have antivirus software that identifies sites that are known to contain viruses and other spam activities.

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The Bottom Line
Avoid being a victim by practicing some common sense. Nothing is free so stay away from anything that says it's free. Don't keep sensitive information on your phone, and stay away from bad areas of cybertown. (For additional reading, check out Money-Saving Smartphone Apps.)

Find out what happened in financial news this week. Read Water Cooler Finance: Insiders, Door Busters And Debt Contagion.