1.   Archaeological sites are often discovered by accident.

2.   And terrorists working alone or in very small groups will be more difficult to detect unless they make a major mistake or are discovered by accident.

3.   Discovered by accident less than a decade ago, the method, called intracytoplasmic sperm injection, or ICSI, revolutionized the treatment of male infertility.

4.   Even Viagra was discovered by accident.

5.   Fort Bliss spokeswoman Jean Offut said the bat colony was discovered by accident recently when workers went in to renovate the building.

6.   His talent as a marksman was discovered by accident when his grade school needed a shooter for a contest.

7.   Pluto was discovered by accident, for much the same reason.

8.   The copies, discovered by accident in a Mexico City print shop, appeared to have been produced so people could alter their cards to vote repeatedly.

9.   The contents of the first of the safe deposit boxes, in a Mexico City branch of Citibank, seem to have been discovered by accident.

10.   The earliest antidepressants were discovered by accident.