I had not seen this movie until this week on TCM. I agree with all the comments here about how good and bad the film is. It has its moments but it also gets pretty stupid.
I thought I would fall out of my chair when George C Scott was arguing with the president and walking backwards in the war room when he tripped over his own feet and fell, did a roll and came up still talking. The stance he struck on getting up almost killed me--sort of like "ta-daaa."
Very funny scene.
Also in the last scene Sellers forgot his lines and stood up out of the wheelchair and shouted, "Mein Fuhrer! I can valk!" Total add lib. Kubrick kept that in too and abandoned the pie fight as a result.