Signs Don't Work! And a solution to one case... (by K)

Over the last 40yrs I've been relatively sentient, I have noticed a gradual but continual rise in the number of signs telling us not to do things.
You know what I mean:

• "Smoking is addictive" - no sh*t - Ah damn. Too late.
• "No user serviceable parts inside" - Hmm. Sounds like a challenge to me.
• "Emergency access only" - with no alarm it'll just be ignored.

And I see very little evidence that they work.
After seeing them the first and second times, they just ignore them.

Example 1 - Emergency Doors
In the building where I work there is 1 single, slow, tiny elevator servicing 2 floors of businesses.
Most people going down to the car-park use the emergency stair well.
And almost all the smokers use it to get to the "Designated Smoking Area."
At the base of the set of stairs is a single door leading outside to the DSA.
And they 'chock' the door open while they have a smoke.
They could walk the extra 30 feet round through the main entrance, but it's easier to 'chock' the door.
And they forget to 'un-chock' it occasionally.
This means the door to the outside world stays 'open' all night - a violation of security and safety.
The safety dudes have installed cameras, placed GIGANTIC signs saying "NOT TO BE USED EXCEPT DURING EMERGENCIES" and repeatedly adjusted that auto-shut lever thingey to force the door to shut.
The problem is that humans are inventive little buggers.
With a new supposedly un-chock proof door in place, everybody figured out, within a day, how to fiddle with the latch thing to chock the door open.
So to avoid a 30' walk, they simply ignore the cameras, ignore the sign, open the door and click in that little thing next to the latch so the door can't shut.
The safety dudes then plastered the door with "THIS DOOR IS ALARMED".
But even the average person can easily see there is no reed switch, so they ignore it.
All to save a 30' walk.

Example 2 - The Coffee Machine
We have a rather expensive Swiss coffee machine in our lobby.
Every couple of hours it does a 'rinse'.
This involves spewing out hot water and milk into the drip tray.
That design choice may seem silly, but the machines aren't meant to spend their lives in an empty un-manned area and used all day.
They would normally be in an area which would have someone to watch over it and empty the drip tray.
Er. Got side tracked.
Anyway.
The point is that since the machine is un-manned most of the time, and the rinse cycle happens relatively frequently, the drip tray overflows and causes a massive mess.
To make matters worse, most of our staff are "young men".
By that I mean: "lazy grubs who are only just getting used to not having their mother to clean up after them."
So we have a plastic beaker that is supposed to be placed under the spout so that the rinse cycle spews into it, instead of all over the floor.
And over the last few months emails and chats and standup announcements have failed to get across the message "FOR PITIES SAKE, PUT THE BLOODY BEAKER BACK UNDER THE SPOUT WHEN YOU'VE GOT YOUR COFFEE."
Signs have been made.
And ignored.

A Proposed Solution:
We have Arduino.
We have Kinect.
We have Speakers.
We have Cattle Prods.
We have Tesla Coils.
We have Lasers.
Can't someone just make a project that detects if the beaker isn't back under the spout as the person starts to leave and give the little buggers a load "OI! PUT THE BLOODY BEAKER BACK" and give their ass a jolt?