What's another way of saying "Just because"?

I'm trying to write something less informal (but not quite formal neither), and I'm forced up against a wall to having to use "just because". But i don't like the way it sounds, any suggestions?

:yawnb:

Depends on what the rest of the thought might be but how about:
due to the effect of
even though

"Despite", perhaps? Depends on the context.

For the reason of? I agree with PabloQ, it really depends on how you use it. :)