Just completed a crosscut and miter sled combination for the 'ol Craftsman tablesaw. I did a 5-cut test (http://https://www.youtube.com/watch?v=RZ_nzvYEZ-4) to get the rear fence perpendicular to the blade - before securing the fence I was .0014" on a 14" cut. That's close enough for my work.
I added 'T' tracks to the bed for some hold downs and a track for stop blocks on the fence. The miter fixture will do 45* angle cuts 'accurately'. Overall, the sled should be pretty versatile and flexible.
Now just need to get to making stuff - hopefully less firewood .