I'm sure there are better ways than this, but this is what I have come up with from what I had laying around.
Take a block of wood and drill several holes at progressively deeper depths from 1" to 4" deep. Check your T-rods by holding a T and claw vertically in one hand and spin the T and watch for any wobble. If you find a bent one, insert the T in a hole just deep enough to where the bend is just at the top surface of the wood. You can usually then just bend the T back straight by hand if the bend is not further than halfway up the rod. If
the bend is closer up by the T section of the rod you may have to use a rubber mallet to tap it back straight.
What do you guys like to use for this?
Here is mine