Here's something cool you can do with screen. Share a screen session with multiple terminals. "screen -x". Of course, this only works if you're using the same user.
Let's say you want to do some cooperative debugging with another username. Simple:
1. Set screen setuid flag:
chmod +s screen
2. Start a new screen sessions:
screen -S mihai
3. Set multiuser
4. Add the user to join your session to the ACL list:
5. Now connect as jimbo and join cmihai's session (called mihai):
screen -x cmihai/mihai
Now you can share you screen session with that user :-).