No when you remove the side shoots from tomato plants you simply compost them.

Actually, you can. I've done it. I merely stuffed the off shoot into some compost in a pot to see what would happen. It grew like a normal tomato plant. And it produced plenty of tomatoes. Give it a try; you've got nothing to lose.

^^^ exactly what i was going to say Digginfit, give it a go, nothing to lose....3" side shoot either in water or in a propagator with bottom heat would be my choice.

Found this info from Gardener's World which may help you Moatrat. They suggest placing in water first until you see small roots forming. I just didn't bother with this step!

http://www.gardenersworld.com/how-to/projects/propagating/how-to-grow-tomato-plants-from-cuttings/4082.html

Hi, when I remove side shoots I usually just leave them on the soil to rot down, and they have on occasion rooted, so actually being inserted in the soil should make it quite easy for them to form roots, Derek.

I'll certainly be trying this, looks a great idea.