Today I've been setting up a Cisco router as a terminal server. One piece is to attach a modem so that we can dial into the router in case the network goes all haywire. In testing out the modem, I called myself with it. When I answered the phone, I figured I should be polite and talk back. Surprisingly, I communicated with the modem.

Here's the transcript:

atz
OK
atdt8675309
CONNECT 1200/NONE
UUUUUUUUUUUUUUUUUUUUUUUUUUUU
NO CARRIER

I've whistled to modems before, but never had quite that much success. It was fun.