I posted this on the tomato forum, but I thought some folks that hang here might be interested as well. Check this out:
<cross-post from 'mater board>
So last year I had the unfortunate chore of moving like 80 tomato seedlings in solo cups across town. What a pain! The cups were in trays, but still were prone to falling over. I made quite a mess in my car and ruined a few seedlings. I've found that managing tomato plants in any quantity in solo cups can be a problem. Anyway, look what I found for this year (and the future)! These are a little bigger than a standard 1020 tray, but who cares....problem solved. Very sturdy. I'm excited...
I'm sure this was meant to be planted in directly, but look how well a standard 18 oz. solo cup fits in.