"Wally, I can't open that file you e-mailed." "Sounds like you need to upgrade your viewer application." "Which means you'll probably have to upgrade your operating system." "You'd better add some ram while you're at it." "But it probably makes no sense to upgrade your old computer. This is a good time to get a new one." "How do I get a new computer?" "It's easy. I'll send you a file that explains it." "Are you sending corrupted files to people again?" "Only if I think they deserve it."