Cut a door in the side and they make great goat shelters or dog houses. Drill some drain holes in the bottom so it doesn't hold
water at all.
If you cut them in half, you can have two cold frames.
They can be used to haul light fluffy stuff (sawdust, straw,
compost, leaves, clippings, etc) in a wagon or truck, more than you normally can hold.
The sides can be cut to make windows for sheds.
There are tons of things they can be used for, it is just what do you actually need that they would be best for.
"You must be the change you want to see in the world." "First they ignore you, then they laugh at you, then they fight you, then you win." --Mahatma Gandhi
"Preach the Gospel always, and if necessary, use words." --Francis of Assisi.
"Family farms work when the whole family works the farm." -- Adam Klaus