Snap to Surface

Is there anyway to have geometry snap to another geometry’s surface along the surface’s normal? For example, making a cube and have this cube on top of another mesh without the cube going into it.

Absolutely.
In the 3D view header, click the magnet icon.
Three new controls appear in the header. The first one (looks like a thermometer on my system) aligns to the surface normal–click it.
The next is a drop-down that let’s you choose what part of the object to align to… select face.
The next lets you choose what part of your object to align… choose center (on the object that you are aligning, make sure the center is at the base of the object).

Now when you are moving something, press and hold Ctrl to activate snap.

Thank you so much.

neve really use this tool begfore

any doc in wiki where it explain more about it

Thanks