Are there any kind of good sandbox games that are free?
The only real good one I can fnd was Garry's mod but I have to buy it and I don't want to spend money right now.

So, are there any good sandbox games out there? I want to know.

S.T.A.L.K.E.R Shadow of Chernobyl is kinda free style,you can explore the area without needing to do quests/etc.
But if you get in dangerous places without needed equipament you get OFC killed...

And yes,it's not free...
But it's really good.

Phun.

http://www.phunland.com/wiki/Home

Algodoo actually.
http://www.algodoo.com/

It is the spawn of Phun.

Sauerbraten has great graphics, and it's a Quake-clone. You also have the ability to make maps and save them, state-of-the-art bots, and most of all, ragdoll physics!
I'd really recommend it and it's really like Garry's Mod.

http://www.sauerbraten.org/

You could try out Souptoys. It lets you play with toys (And build) and a 2D enviroment at your desktop. It's nothing like Garry's Mod, though.