Gracefully logging off another user.

[Colin Murphy]

On my home, family machine, members of the household are quite happy 
to 'Switch User' and open up a session for themselves - they seem far less 
happy to log out again at the end of a session.  This usually means there are 
several, three, maybe four, active sessions running on the one machine.  If 
one of these sessions has some processor intensive task running, say they've 
left a browser on some flash rich page, system response times really plummet.

Instruction and education to family members, some times with a larting stick, 
has not reaped the rewards one might have hoped for.  So ...

What is the most graceful way, as a super user, to log out another user 
closing all of their processes and ending their session?

-- 
Colin at Spudulike.me.uk
Gotta go, things to be, people to do, and stuff to, err, stuff.