When the Acer projector I have is on, but not connected to an input, it displays the Acer logo. Is there a way to replace that logo?
Unofficially, you could put custom firmware on the controller in the projector. If it's a nice enough projector to have a firmware update process then you "only" have to hack the firmware. If it doesn't have a built in update process then you'll also have to figure out how to do that, probably through some trickery with additional debugging hardware.