In 1994, Intel recalled its Pentium processors to repair a bug in its floating point division instruction, FDIV. Here's an example of the bug:

4195835.0/3145727.0 = 1.333 820 449 136 241 000 (Correct)

4195835.0/3145727.0 = 1.333 739 068 902 037 589 (FDIV)

It may not look like much, but Intel estimated that this recall cost the company 475 million dollars.