I worked at a place where the kitchen had a little tradition of pulling pranks on people on their last day. It was a seasonal job, so everyone had a last day and there was no ill will about it being their last day. This one guy, these other guys mobbed him and stripped him buck naked, tied him to a chair, saran wrapped him and left him there for someone to find. oh, my.

You know the water activated heating packets that come in MREs ??
Oh..you don't? Well trust me on this. You add water to the packet and it heats up. Also gives off hyrdrogen.
ANYWAY.....Put some ground up packet powder in an empty 20oz water bottle. Add a little water. Put on the cap (tight) and hide in a trash can...After about two minutes the bottle will explode(well pop loudly anyway). See if you can convince everyone it was a rocket attack and they should run for the bunker....
Why isn't anyone laughing???

i put those "do not eat/silica" packets in my co-workers candy dish.

bullion cubes work well too.

Believe it or not, the Navy was great for workplace practical jokes.

all of our office phones look like this:



1) so, fun with telephones, game one: take the keypad off the boss's phone and rearrange which wire goes to which number. So every number dialed would be a wrong number, if it'd connect at all.

2) more fun with telephones: unscrew the lower part of the handpiece (we had some really old phones) and remove the microphone part. Some guys would scream and scream into the mouthpiece.

3) In the maintenance hangar, we'd ask the new guy to "go to the engine shop and get the 'one 'D' ten tango' manual." Sounds very offical, so they'd dutifully go in search of it. But of course the engine shop wouldn't have it, and the poor soul would be sent somewhere else. Often we could get guys running all over the hangar and sometimes the entire base looking for this manual.

It's only when they'd write down "one (1) D (D) ten (10) Tango (T)" -- that'd they'd see it spells 1D10T -- or simply, IDIOT.

great fun - and there are many more.

Found a really cool program that will randomly open the PC user's CD drive, make a fart sound on the speakers, & close it again.