10 most important security-related events?

Hi all,
I’ve been trying to formulate the “top-ten” list of most important facts from field of security over the last few (10 maybe?) years: be it algorithmics, hardware, software, cryptography…
So far I’ve got breaking SHA1, MD5 and WEP, introducing bilinear functions to the field, and … run out of ideas. Help will be greatly appreciated.
Cheers,
PB