The "simple conclusive" answer is screen. I know you've said you don't want screen, but I'll give you the simple steps anyway:
- Log in to the remote machine using SSH
screen (your command window will look like it's been cleared)
- Run whatever command you'd like. No need to use &
- Press Ctrl-A, then the D key
You'll be disconnected from screen, and your command window will look like it did when you logged in, though the process will still be running. Using screen also gives you the advantage of being able to reconnect to the running process after disconnecting your remote machine, which nohup will not allow.
As far as using nohup goes, I haven't actually used it, but the syntax appears to be simply
nohup yourcommand &. It's worth pointing out that the Wikipedia article on nohup offers a number of other alternatives you might want to try out, such as
VNC if it's available, or
start-stop-daemon on a Debian-based system.
EDIT: If you'd like to start the process in a single line, you can use
screen -dmS name yourcommand, where "name" can be anything, and is simply the name screen uses to refer to the background session, and "yourcommand" is the command you want to run in the background.