Okay, thought I would share my stupidity with the world.
I was cutting down a piece of 1/2" ply. Had it sitting on top of my table saw. Was using my circ saw. Not paying close enough attention. I saw sparks. This can't be good. Cut about a 1/2 inch off the end of my aluminum rear rail for my TS. My Diablo blade sliced right through it like butter.
The sparks came from the tip of the screw holding the end cap on the rail. Luckily it was a small enough amount of rail not to matter, and it was nearly a perfectly square cut. Not noticeable unless you were looking for it.
That's all.