@billion57 (View Post)
Phun/Algodoo is really awesome

@billion57 (View Post)
Powder Game. Incredibots 2. OE-Cake.

Minecraft.

@randalserrano (View Post)

@billion57 (View Post)

Anglodoo Is the best I know. Minecraft is more survival and a game.

@billion57 (View Post)
Laputan Blueprints is best. It's free, 3D, uses bullet physics- so that means Air resistance, water resistance and friction resistance - along with centrifugal physics.

download it here:
https://sites.google.com/site/laputanblueprints/

It's more of a vehicle simulator though, you can make cars, planes, boats and whatnot. Which is quite fun.

If you want a full-on vehical simulator, that is modable, try RoR. It requires a good comp though.
You can dl it here-
http://www.rigsofrods.com/content/?s=d95811980707ceec1f4f883190326a55
it's free, but very big.

Also, something better than oe cake is Physios studios.

This game of course!