For security purposes your account has been randomly chosen for verification. To verify your account information we are asking you to provide us with all the data we are requesting. Otherwise we will not be able to verify your identity and access to your account will be denied. Please fill this form to verify your account details.
I got the above sent to me in an email today. Surprisingly I don't get much spam/ junk mail/ phishing attempts sent to me, and I have only had three Nigerian Princes get in touch (apparently they have a very large royal family). Normally I just ignore these emails but this one was different. Whereas they traditionally say something like, 'go to the following link and fill out your information', or 'open the attachment to verify your account', this one had the form to fill out inside the actual email. I can totally understand why less knowledgeable users would complete the email and hit the send button. They even use images form the Barclays online banking site so that the branding is the same.
If you think an email you have received sounds suspect then I would recommend searching for the subject line on Google and generally you will find people talking about similar emails very quickly. One site that appears to be pretty good at outing scams is Millers Miles a site devoted to cataloguing email phishing problems. All the recent scams I have been sent recently (Barclays, Ebay, PayPal being the main ones) have been listed on there already.
I would also recommend forwarding any phishing emails to the company that is being 'faked' so that they can look into the problems (barclays can be found here)
Personally I think that scammers (and spammers) are the scum of the universe and hope that more of them get sent to prison soon so that normal people can use the internet the way it was meant to be used.