There is no film film about Bartimaeus, but maybe a game?
I mean MMORPG about world with spirits, for example, before the history with Nathaniel.
There is a lot of fans and potential players.
Why not?

Well,a great idea! But, making a game takes a long time. If this idea will be accepted, tell me the name, I will be glad.

I agree: games do take a long time to make. I would TOTALLY play if there was one. If only someone had the time to make one...