Acceptable reasons for bothering me while I’m writing include: 

1. Blood, death, and/or dismemberment (and if it’s dismemberment, it better be important parts. No pinky toes, or fingertips)
2. You have the perfect plot point to get me past my writer’s block
3. You bought me a box of warm, fresh-from-the-bakery doughnuts
4. Hugh Jackman is at the door, asking for me (would also accept Chris Hemsworth or Ryan Reynolds)
5. The Publisher’s Clearinghouse people finally showed up with my giant novelty check  
6. A special off-season episode of Game of Thrones is running (like, now)
7. The house is on fire (and it better be a BIG fire, right outside my office--because if it’s only a small fire at the other end of the house, I’ll be pissed)
8. You want me to piss me off (note: this will result in you being killed off--horribly, embarrassingly--in my next book)
9. Stephen King is on the phone and wants to give me his secret for publishing so many brilliant books so fast
10. The giant spider in my basement (aka: the Source of All Evil) invited his friends over, and it’s time to surrender the house to them