...how about sharing the offending email address so we know what to look out for? Dumbbell eBay is putting attachments on their emails for bid confimations and some sellers using 3rd party auction services are sending invoices using attachments. The point is, a lot of thoughtless attachments are coming so we need to know what Markman's email address is so's we can pick it out.

Here's a method I use if I send an unsolicited attachment, I send a note first stating I'm sending a .jpg or whatever so the attachment will be expected.