Peter Van Ooijen responded to a question i asked about getting tablet pen tilt information with a great blog post : Tablet PC pen capabilities and the tablet API. the results are that his tablet says it can get the tilt info ... but it just returns 0. this is the same behavior that i've seen as well :(
anyway, why do i want pen tilt info? simple reason ... old school video games. you could basically set your pen perpendicular to the screen. then you could control a character by angling the pen like you would a joystick. if you needed to do some action, either tap on the screen, or press the button on the pen. you could certainly play alot of Atari classics in the manner. oh how i miss River Raid ...