Had one this morning from Florida Car Hire Company. I have actually been dealing with them about my visit in April. But...I did actually take care to right click to get "message scource" and right at the bottom was the giveaway. I caught sight of the word Napster.MP3.pif and remembered it was amongst the list I had been memorising from McAfee. Then I burned it.
Then I told the company that "sent" it that they are infected.
Haven't heard from them yet.