You can't make this stuff up...   I snapped this pic with my phone yesterday:

1. One of your coworkers bet someone.  "Hey, I bet you $100 I can jab a huge safety pin in Bob's collar without him noticing."
2. One of your coworkers tried to jab a safety pin in your neck, but missed.  "Hey Bob, your tie is crooked.  Lemme fix it...  DAMMIT."
3. The guys from Myth Busters were debunking the theory that you could kill someone with a homemade giant safety pin launcher.
4. He's one of those old guys that wears his pants too high, and there's another safety pin on his belt that also broke.
5. For all you Matrix fans:   "There is no safety pin."
6. Its a Delicious/AARP joint venture to tag all the old guys.  His tag fell off, though.
7. He's The Fly's dad, and he accidently got into that big teleportation pod with a big safety pin.
8. He's trying to start a trend.  All the cool people are wearing big safety pins in their collar.
9. He's so cool that his collar naturally goes up, and he needs the safety pin to keep it down until after hours.
10. He's always forgetting his briefcase around, so he usually keeps it safety pinned to his collar.