Failure mode of FLASH memory
Here's a project designed to destroy an EEPROM by writing to it repeatedly:  Flash Destroyer

According to the comments, though, it's not a particularly good demonstration:


  I am guessing that this test will actually not show the real problem very obviously, or should I say early. Since I think the real issue is that the data retention time will drop with number of writes. I.e. after 1 million writes it will store the data for a number of hours specified in the datasheet.
  Eventually the data retention time will be so short you will see problems, but in real-life, problems with lost data would occur much earlier.


I also asked a similar question on SuperUser: What happens when a flash drive wears out?