Geek pranks: 15 high-tech tricks to haunt your co-workers

In every office, there's the guy who has no sense of humor and hates the idea of having fun. If you're that guy, you should probably stop reading this now.

Still with me? Good. You see, the thing is, seriousness is overrated. Sure, there's a time to be focused and professional. But there's also a time to be silly and immature -- yes, even when you have an impressive 10-word title that no one but you understands. (Sorry, Senior Supervisor of Quality Control and Other Specific Duties. I'm sure your job is very important.)

So that's where these geek-friendly pranks come in. With this list, you'll have more than enough tricks to balance out the treats floating around your office this Halloween. Every workplace needs its resident prankster, and this is your chance to step into those shoes with style.

A few words of warning: Some of these pranks will require you to edit advanced settings within your operating system's configuration. If you aren't familiar with those settings and make a mistake, you could really screw stuff up. And, equally important, if you cross the line between good clean fun and mean-spirited antics, you could really make someone mad.

To sum up: Proceed at your own risk and only if you feel fully comfortable with the steps involved. Prank often, but prank wisely. And, for the love of God, don't tell anyone I'm the jerk who put you up to all of this.

Capisce?

1. The Sound of Amusement

Let's start things off with a bang -- or, to be more accurate, a baa. For our first prank, you'll catch your cubicle neighbor off-guard by toying with his system sound files. Changing the sounds altogether is too obvious; instead, edit the existing sound files to add unexpected noises at the end.

The Process:

Using a simple WAV editor like Audacity, open a commonly used system sound file such as the e-mail notification alert (typically found in the Media folder within the Windows directory). First, add 15 to 30 seconds of silence to the end of the file. Then, after the silence, tack on the sound of a sheep baaing, a fly buzzing, or whatever else tickles your funny bone. (You can find plenty of free sound effects on sites such as WavSource.com and SoundAmerica.com.)

Drop the finished file into your co-worker's Media folder, using the same filename as the original. Make sure to back up the old file first so you can restore it later.

The Final Product:

The next time your co-worker gets an incoming e-mail, your strange sound will follow -- and, thanks to the built-in silence, it'll be distanced enough from the normal sound that he won't know what hit him. How baaaad is that?

2. Temporary Insanity

The Prank:

Imagine if tiny sticky notes were constantly flying onto your desk and filling it with clutter. Now imagine the same effect happening on your computer's desktop. It'd drive you crazy -- which makes it the perfect premise for our second prank.

The Process:

Sneak into your work buddy's system settings and edit the location where temporary files are stored. Enter the Windows System Properties menu (right-click on My Computer, then select Properties). Select the Advanced tab, then click the Environment Variables box. Make sure the line that says TEMP is highlighted, and click Edit. Change the Variable Value to the desktop path (commonly C:\Documents and Settings\All Users\Desktop).