Have you received an email with the subject "Airmail Tracking number #8154506" today? If so, don't open the attachment as it's the latest disguise being used by internet hackers to infect your computer with a Trojan horse.
"Airmail express" messages have been seen in large quantities in our spam traps worldwide in the last hour or so.
The emails typically read as follows:
Unfortunately we were not able to deliver postal package you sent on August the 1st in time because the recipient's address is not correct.
Please print out the invoice copy attached and collect the package at our office
Your support invoice number #3521120850144467
Inside the attached archived file, #876712.zip, is a malicious Trojan horse. Sophos has been intercepting the emails as spam with our email gateway filtering products, and has just issued detection for the malware as Troj/FakeAle-GN.
No-one should need reminding, but it's worth reiterating. Always exercise extreme caution and think before opening unsolicited email attachments.