The Coming Software Patent Apocalypse

Jeff Atwood, back in 2007:

Patents give their owners the right to prevent others from using a claimed invention, even if it was independently developed and there was no copying involved.

Think about that for a minute. Seriously think about it. Every time you write code -- even a brand new algorithm in a clean room environment-- you could be infringing a patent, somehow, somewhere. That's why it's so often described as a software patent minefield.