collision response

Hey all, I''m wondering if there''s a generic formula for a collision response to glide/strafe along a wall that it has collided with...or something similiar. I checked in my 3D Math book for collisions, and it says how to detect, but not what to do afterwards. Basically, when I hit a wall, I want the user to keep moving -- be it gliding down the wall in the closest alternate direction they were facing, or rotating the camera to the closest other direction they were facing... I think my main question is...how do you tell which direction to rotate/move? My Camera/Player has a Position and View vectors, but in my trial-and-error (do something and see what happens) pulling coords from those Vectors haven''t been helpful at all. What am I missing here? Right now, on a collision, I rotate to the left -- simply because I''m not sure how to detect if it should rotate to the right instead. Thanks!