Drywall going up: how far to place ceiling projector connections?

[Tahoe Gator]

I am finishing my basement and want to pre-wire for a ceiling mounted projector, which I have yet to buy and do not know which model I will. I am pre-wiring power and all of the connections and would like to know the ideal distance from the screen to locate the junction box. I know the answer is 'It depends' but with out knowing anything more, what is the best/safest distance to locate the connections? Thank you.

[N. Abstentia]

I put mine at 18' from the wall, but I didn't figure that out until I got my projector. Each one is different!

[AVMASTER]

without knowing the projector model we can only guess, i'd run a conduit from a centralized spot on the ceiling to equipment/power location; with any luck it won't be too far from where the projector actually needs to be.