I am making 12 animations for a friend.  Many of the scenes have complicated lighting or textures that take my machine forever to finish.. Example:  still ocean scene with intensive faom textures.  Above the ocean are some stars.  They need to twinkle.  This is being done for HD and needs to look good.  My machine currently takes almost 3 hours to get through the waves.  Deadline is looming.  Any ideas?