
Although I am getting
a little machine oil, I think it's metal.
The Big Bang Theory Season 9, Episode 18

Although, now that you've point it out,
it is undeniable.
The Big Bang Theory Season 10, Episode 11

Although, now that I think about it...
The Big Bang Theory Season 8, Episode 9

Although what I lack
in leadership,
The Big Bang Theory Season 5, Episode 1

SHELDON:
Although, on one occasion...
The Big Bang Theory Season 4, Episode 3