The humor site Segfault.org has this item: "The Exchange virus/trojan poses as a MTA/MDA server. It is currently distributed on CD only. It costs
between $1500 - $5000, typically, although some versions cost much more.
Once installed & deployed as a mail solution, the exchange virus will periodically crash, causing you to lose
all your data. When you perform the "maintenance routines" specified by the creator, it can randomly crash
as well. The virus is designed to prevent any back-ups of your data from being successful."