There are a handful of Bluetooth modems out there, but there's no support for serial Bluetooth before Android 2.0. Running a phone with 1.5, I can't see if anyone's put a terminal application in the market that supports it.
I suppose you could hang a modem from something you can get to via SSH. That would keep you from having to find a phone line and would let you do the same thing from anything with an Internet connection and an SSH client.
--Mark