If your email address has a "m" in it, you can try to send an email to
a co-worker, disparaging your boss. cc it to your boss, but change the
"m" to "rn". Pretty funny, until they catch on.
The other is to change the sounds in his Windows setup. We used
farting sounds, long juicy ones. Absolutely hilarious results when we
did it to one of the upper managers.
He would leave his office with his laptop unlocked, but a 1 minute
timeout (so he figured he was safe). He left, his secretary called us
and we had the .wav files ready to go. Changed the open/restore
window, close window sounds to the juicy farts.
Anyways, what we didn't know, he had stepped out to pick up a
VP coming in from Toronto, and was bringing said VP back to his
office for a meeting requiring him to open and close many many
windows.
I had to leave the office (for real) and the secretary watched in
horror as they went into the office and he unlocked his laptop.
Then he opened the first window...and sat in stunned silence, as
did the VP. Then he shrunk it, opened another...and again...ad naseum.
Then he began to apologize to the VP, over and over. And then figured
out how to mute the laptop.
The VP, however, did see the humour in it all.
However, after the VP left, he came out looking for me, yelling my name
down the hallway. (Why me!?

)
When I got back, I was warned to call it a day, manager was on the
warpath, and had my name. So I did the manly thing, and ran.
Next day, he had finally found the humour in it, and I was off the
hook. When I asked why me, he said, "Who else would time it with
the VP?" Even though I protested I had no idea the VP was coming
in, he didn't believe me.

We had a good laugh as he described
thinking, "WTF?! Uh, this can't possibly be the best time for this!"
as the VP sat across from him looking blankly. My co-worker
pal and the secretary were more than happy to let me take the hit
on that one.
ers