I have just noticed that 1000000000, using Unix timestamp is Sep 9 01:46:40 2001 GMT. Just two days before 9/11.
Got another one for you:
1111111111 = 03 / 17 / 2005
Just two days before:
"March 19 A time bomb explodes in a Muslim shrine in Quetta, southwestern Pakistan, killing at least 29 people and wounding 40"