I'll be watching this, I have a green one that DH just can't throw out :-)

Yes, you could do that as long as you weight the bottom or, if you really want to use it as a sprayer, you can buy replacement parts and it will most likely work like new.

I think it would make a great base for something ( I would have never thought of that, in fact we threw some old ones out last year) You could fill it with rocks or sand or concrete.
Garden ball stand, birdbath bottom, totem bottom- great idea. Have fun and keep us posted. (Inquiring minds want to know...)
Btw, have you noticed it looks like a penguin?

Not to be negative but I wonder how long the plastic will hold up without cracking? I had a couple of plastic items outside for the last 3 years and was very disappointed when I went to move them they cracked and fell apart. Maybe there is a coating you can spray over the plastic to keep it from cracking.