In Blender Internal, there's an option in the Particle System Texture panel to let the texture affect the Size of the particle. But nothing for the Rotation. A gradient texture can be used this way to control the size of a particle as it is spawned, lives and when it dies. Having a particle rotate when it is spawned but stop rotating after awhile, or slow down and speed up the rotation speed (of each individual particle, not the whole system) doesn't seem to be possible because of the above reason.
Is there any other way to do this?