1. Fire, both house and forest. Forest is less than a mile away.
2. Long term power cut.
3. Long term gas shortage.
4. Nice young RAF chap dropping his Tornado in my back garden.
5. Accident while away training.
6. Maniac farmer with muck spreader.
7. Terrorist attack.
8. War

I'm less but still noticeably concerned with random crime and suitably versed with WMD's to take them quite seriously.