'Did you see this video of you? Check out this link!'

This is another popular scam. Security experts are seeing an increase in such spam, especially on Twitter, the popular microbloging site.

A recent spam campaign on Twitter read: "Did you see this video of you?" Thinking it to be from a friend many users ended up clicking on it and landed up at a fake Twitter site. Once there, unsuspecting users entered passwords, which then ended up in the hands of hackers.

'Please confirm this order'

Another popular scam is fake invoices. Here's how this scam works: The bad guys create a fake invoice and sends it via email as an attachment. Once the user opens the email attachment, there are a few variations of it. The recipient may be asked to confirm or cancel an order, they may be told that the parcel service was unable to deliver a package due to incorrect address, or the recipient may receive a customs notification about an international package. In all the cases, the order appears as a great bargain.

In every instance, the email either asks users for their credit card details so that their account can be credited or requires the recipient to open an invoice or customs form to receive the package.

'Check out our new Discount menu'

Many retail sites offer discounts during the festive season or during changing season(popularly called off season discounts. Casing on these, spammers try to send mails to lure people to enter bogus sites and reveal their credit card details.

The fraudsters clone a retailer's site. And when a user clicks on the fake voucher, they are taken to this site, and prompted for login or credit card details, which the criminals then use to carry out identity theft.

Recently, Websense Security Labs discovered infectious emails wherein victims were receiving messages promoting a coupon from McDonald's or a holiday promotion from the Coca-Cola company. Both messages include a .zip attachment that contains either coupon.exe or promotion.exe. The malicious files are Trojan Droppers.

While the McDonald's email claims to present their latest discount menu, and states that the attached coupon should be printed; Coca-Cola email states that the attachment has details about their new online game and a chance to win Coca-Cola drinks free for life.

'I'm traveling and I've lost my wallet. Can you wire some money?'

The popularity of social networking sites has given a new platform to scammers. A recent scam according to experts involves the fraudster posing as a Facebook 'friend.' They send a message or IM on Facebook claiming to be stuck in a foreign city and they say they need money.

Ironically, many innocuous social networking site users fall to such SOS mails, and wire money.