Wink-winking and nudge-nudging aside, pranks at the office can be tricky to pull off. Before you start scheming, keep these work-friendly guidelines in mind: be sure that your prank doesn't violate any legal rules of conduct or unspoken rules of etiquette, doesn't disrupt the workplace in a significant way, damage company-owned equipment, or truly embarrass anyone. You know your workspace and your fellow coworkers –- people want to have fun; no one likes to be made fun of. Use your judgment!
Rearrange the items in her desk. Before your coworker arrives to the office, raid her desk for papers, books, folders, and supplies, and shuffle their places. For extra evilness points, relocate them in weird places all around the office.
Tap(e) the phones. Tape down the phone button (the one under the receiver) so your coworker thinks it's not working when she picks up the phone.
Have fun with Photoshop. You might want to enlist the help of your office's graphic designer for this trick: Borrow your coworker's desktop photos of family and friends, scan them into photo-editing software, and retouch them with face-in-hole effects, human-to-animal montages, and celebrity cameos ("Wait a minute, who swapped all of my friends in this picture with Martha Stewart?")
Make time for a coffee break. Or a coffee spill, that is. With solidified paint, you can fake a spill on her desk, chair, or -- if you really want to freak her out -- laptop keyboard. (And if she takes milk with her coffee, make it magically unpourable.)
Did you get the memo? For that one person in the office who always seems to be the last one in-the-know (or blatantly ignores them), here's the perfect prank idea: Cover your coworker's desk (including computer, swivel chair, phone, books, and shelving) entirely in post-it notes.
Control the cursor. It'll be all fun and games until the IT guy shows up. If you share desks with someone, control your coworker’s computer remotely. For a desktop computer, add an extra mouse (controlled by you) to a USB port. For a laptop with a wireless mouse, swap hers with one that's nearly identical but under your control. Just make sure she isn’t as tech-savvy as you or the jig is up!
Bug someone (literally). Is someone notoriously afraid of creepy-crawly critters? Plant a fake roach in her drawer, sit back, and watch her bug out.
And if all else fails, there's always the old "stapler-stuck-in-jello" trick. It makes a crowd-pleaser and, at the end of the day, who can stay mad at free dessert?