A couple of years ago there were scam UPS emails going round - telling you they had been unable to deliver and asking you to open an attachment to read the details - when you did a nasty virus jumped into your computer.
Today I received an email supposedly from Fedex saying my order exceeded the free delivery limit and attaching an invoice for the unpaid carriage. I was expecting a couple of deliveries and nearly fell for it. Luckily I smelled a rat and phoned Fedex - turns out they know about it as loads of people have reported it and loads more have found their computers suddenly infected.
BEWARE
