how to fake activity to avoid standby

Hi

Is there a method to auto fake activity to avoid computers going into standby? I am monitoring several computers from one keyboard and, due to the security in my office, the blasted things keep going into standby and have to be restarted by a different password login for each one. I have managed to achieve it on some by playing a windows media file on repeat, but this method is not working with all of them because they are on different systems. Any ideas please? I cannot alter the settings due to being denied access, and will not be allowed this ability.

Thanks
Steve