[markedathome]

hu hum...digs out "Managing UUCP and Usenet" by Tim O'Reilly and Grace Todino, revised 1994.

p293 " ! Should only be used when sending via UUCP. This should be the only special character in the address (called a path). The path indicates each site through which mail will be routed, starting at the left and going towards the right. Mixing ! with @ is not considered good. That is, use:

uunet!ucbvax.berkeley.edu.edu!smith

not:

uunet![e-mail]"

In other words because UUCP was dialup and long distance expensive, email was routed through specific known hosts, which is why sometimes people ended up with long bangpathed addresses.