Making someone remember to lock their computer through negative reinforcement

[1stRaven]

While there are plenty of amusing suggestions here, I'd take the formal/official route otherwise your actions could be interpreted as pranking or bullying - and land you in trouble too.

Does your workplace have a published Acceptable Use Policy for the internet? Is he breaking it? If so, report it to your HR department and let them handle it.

If not, and you both report to the same manager, report it to your manager and let him have a quiet word with the intern.

If you're a SysAdmin at your workplace, implement a Group Policy that sets a Screensaver Timeout, along with a Screensaver Password. Set the timeout to something sensible like 15mins... or 5mins if you're feeling evil.

If you have any general-use kiosk/public facing/conference room machines, make sure the GPO is not applied to these machines (you can always use a Deny Read on the GPO object for those individual machines).

My .02c!

+1. I am a sysadmin (in a way - at least in charge of 4 of them). Doesn't your IT dept have a group policy in effect for this already, if locking your machines is a company policy?

[Pob255]

If he's from the governments new slave labor or we take away your job seekers allowance thingy scheme, then you've got what you paid for

If not then give him a couple of days and if he's still not changed kick him out.

Ok that's a bit more extreme than I'd normally be, but it sounds like he's got a really cushy placement and good opportunity and is just pissing it away.
It annoys me because there's plenty of people out there who would be willing to jump at that opportunity.

[Butuz]

So you've given this waste of blood and organs domain admin access???

First thing I would do is revoke that access.

Second thing I would do is give up wasting your time fiddling with his pc and his Facebook and start disciplinary procedures. Take it higher if you need to but follow your company policy and verbal > written > final > goodbye sir.

Butuz