You can see the MATRIX, can't you?
The Big Bang Theory Season 1, Episode 12
You know how I know
we're not in the Matrix?
The Big Bang Theory Season 2, Episode 2
He recommended that I go see
the third Matrix movie...
The Big Bang Theory Season 4, Episode 7
Multiplied by a MATRIX
of negative I comma zero...
The Big Bang Theory Season 5, Episode 7