I make chunky salsa in 2 quart batches. I have terrible knife skills, it takes me way too long to dice the amount of tomatoes needed for a batch. I am looking for a piece of equipment that will chop or dice the tomatoes into appox. 1/4 inch pieces in a quick and efficient manner. 
I cut the things in thick slices and put them through a french fry cutter. That gives me nice tomato cubes without much hassle.  Incidentally, the cutter works great on peppers, bell etc, too; nice square bits, little effort; plus of course you can make french fries or cottage fries. 