A friend of mine got me hook line and sinker once with this:
About 10 years ago or so, VH1 (or MTV) was having a contest to give away a slew of Corvettes. My friend entered it, and promised me (and a few other friends) one each if he won. I stayed at his place for a weekend for some reason, and one afternoon, while he was at work and I was lounging around the house, the phone rang. I answered it, and it was someone calling to confirm my friend’s contact information in for the contest, and left a message for him to call them back. Frantic, and excited, I called him at work and told him all about it. He was too busy to call the contest people back then, so I had to wait until he got off work for him to do so. By the time he got home from work, I had worked myself up into a lather about it, and he confessed to having a co-worker call me about it. He was planning on dragging it out for a few days, but was too amused at my reaction to continue it.
I’ve always thought about getting back at him by having a lawyer friend of mine draft a letter to him asking him for paternity money for one of his ex-girlfriends…
Some good computer related practical jokes:
Put a piece of tape on the bottom of the mouse, so the ball doesn’t track.
Remove the ball from the mouse.
Rename the big file that they’ve been working on for months.
Change their word processing spell checker to British English.