Its easy to change the string on the FTDI-based Ardunios with the Dangerous Prototype's pirate-rename application. Having the abililty to apply custom hardware names certainly makes it easier to figure out which Arduino you'd like the talk to in the case that you have more than one.
However, since the Mega 2560 does not have a FTDI chip, I'm looking for information about how I can change the identifier string it reports via the USB-Serial connection. For instance, it now appears as /dev/tty.usbmodem1d21. I'd like to at least change the 1d21 if not the entire string after "usb".
How would I accomplish that? Is it in the EEPROM? If so, which location?