Plant the piece that snapped off and it might root and continue growing into a productive plant. At this point I'd plant it into a pot of soil rather then the ground so that you can keep it warm and watered. When it looks like it has recovered and growing, plant into the ground.

Like rhoder said, try to root the broken piece, by lightening up the leaves on it.

There is a good chance that the mother plant will re grow branches from where you have previously removed suckers.

Sey

What a great idea to plant the top! I have never heard of that nor tried it, but it makes sense.

As for the plant itself, I have a friend that grows Earl's Faux. He planted and had rabbits come in and clean the tomatoes off clear to the ground, leaving only stumps. Those tomatoes regrew and produced lots of tomatoes. Although, they were a little late, the harvest was abundant. I have had hail storms come through and cut off the tops of all of my tomatoes and they survived and went on to produce a huge crop. There is a story around town that a woman's grandmother takes a broom and stirs up her tomatoes every year... Beats them up really good. She says they produce better when she does. Ha! I wouldn't try this on purpose (well maybe if I had an extra tomato, I might), but tomatoes want to grow. That's been my experience. :) Send us pictures of the harvest!

Rebecca

Your plant will grow new branches and continue on as if nothing happened.
And removing "suckers" is unnecessary unless you are growing them in limited space and have the plants close together.

Rodney