Written by lifehacker

Since the dawn of time, geeks have been playing harmless pranks on their beloved (but unsuspecting) associates, and it’s up to all of us to carry the torch forward. On the eve of April Fools’ Day, when you’ve got local network access to your coworkers’ and family systems, cubicles just crying out to be filled with packing peanuts, and webapps that can do all sorts of things automatically, there’s no better time to baffle, confuse, perplex, and just plain mess with your loved ones and associates. Hit the jump for our top 10 favorite harmless geek pranks, just in time to get your prankster pistons firing for tomorrow.

10. Install the Blue Screen of Death Screensaver

Make your co-worker think their PC crashed when they get back from lunch. The BSOD (“Blue Screen of Death”) screensaver is a free download from Microsoft (ironically.) For other operating system “support,” check out the Linux BSOD ‘saver with support for Apple, Windows, and Linux crash screens.

9. Fake a Desktop with Screenshot Wallpaper

Freak out your co-worker or family member by faking out their Windows desktop with an unclickable facade: Take a screenshot of their current desktop, then set it as the desktop wallpaper. Hide the actual taskbar and disable desktop icons (right-click the desktop and choose “Arrange Icons By” and uncheck “Show Desktop Icons.”) When your victim returns to the computer, watch the futile clicking begin.

8. Schedule a Phone Call with a Text-to-Speech Message from Wakerupper.com

Wake up calls aren’t just for the a.m., you know. Pop your victim’s phone number, a time, and a custom message into Wakerupper.com, a free wakeup call service, and they’ll get a call with the message read Silicon Sally text-to-speech style back to them. (original post)

7. Fill an Office with Packing Peanuts (Or Make It Look That Way)

Actually filling your co-worker’s cubicle with packing peanuts can be a pain in the ass, but if there’s a glass wall involved, it’s easy to make it look like you did. Check out Hack N Mod’s nifty gallery of what looks like a glass room filled with packing material.

April Fools: Cubical Chaos Fakeout [Hack N Mod]

6. Remote Control Your Co-Workers’ Computer with VNC

How would it feel to have your mouse taken over by a ghost and do things on your computer you never intended while you watched? You can inflict this feeling of utter confusion on your victim using VNC, a computer remote control protocol. You’ll need to install the VNC server on your victim’s computer first, and have their IP address, so this one will work best in the office when you’re on the same network. Here’s how to remote control a computer with VNC. Mac users, here’s how to remote control Leopard with TightVNC.

5. Message Co-Workers with NET SEND

Hidden in the depths of the Windows command line is a nifty little utility called Net Send, which pops up very official-looking alert messages on any computer you send them to. If you know your co-workers’ IP address, you can net send them goofy messages, like this person on the Geeknewz boards:

A good prank that I have played on some friends involves the net send command. What I did was I used the net send command to send a message that said “Microsoft has detected that you have a small penis. Please consider upgrading for better performance” to other people on my local network. When you use the net send command in the command prompt, you specify the computer you want it sent to by typing the computer name, it also says on the message which computer it came from, so I changed my computer name to Microsoft, so it appeared, to the technically challenged, that the message actually came from Microsoft. In case you were interested, the syntax for the net send is:

net send computername message

Here’s more on how to use net send.

4. “Break” Your Victim’s LCD Screen with Wallpaper

Want to put a crack into that shiny new widescreen monitor? Download the broken LCD desktop wallpaper, set it as your victim’s desktop wallpaper and hide the taskbar and icons.

3. Hijack Firefox with the Total Confusion Pack Extension (Enabled on April 1st Only)

Your victim use Firefox? Install the “Total Confusion Pack” Firefox extension, which enables the following “features” on April 1st only:

• Two Steps Back: Make the back button go back twice-not every time, but only on random instances.
• Rick Rollr: Switch out 2% of the video clips your victim watches with the infamous Rick Astley video.
• The Devil’s Inbox: Make the number of unread email in your victim’s Gmail inbox exactly 666.
• Highs and Lows/Sarcarsm Enhancer/For real: Add LOL, *sigh*, “for real,” “Whatever” and various other commentary to web page text.
• Watch it: Make it look as if the page was loading forever. (Now this is just plain mean.)

Download the Firefox Total Confusion Pack here.

2. Customize the Office HP Printer’s Console Message

Baffle your coworkers with an “Insert Coin” message on the office printer using the HP Printer Job Language (HPPJL) command set. Here’s how to customize the printer’s Ready prompt to read whatever you want. (original post)

1. Turn Web Pages Upside Down

If your office or housemates all use the same Wi-Fi network and you’ve got some network admin skills, run the web traffic to their computers through custom scripts that turn images upside down, blur them, or redirect all web page requests to kittenwar.com. This is the most difficult trick in the list to implement, but it’s pretty clever. Here’s more on how to set up Upside-Down-Ternet. (original post)

For more good pranks, check out Wired’s Top 10 April Fools’ Pranks for Nerds, and Ask MetaFilter’s thread on the topic.

What’s your pick of favorite April Fool’s Day prank? Share the love in the comments.