one uv map for multiple objects?

i’m wondering if its possible in blender to make one uv map for multiple objects, im assuming it is; how would you go about doing it?

especially since the new version of zbrush can combine multiple textures into one big mega texture and unity looks like it relies pretty heavily on the same technique

The easiest and quickest way is to join all your objects to form one single object, unwrap and then separate them back out again.
Apply all unwrap seams to each object before joining
Select them all and join with Ctrl+J
Go into edit mode and unwrap with U / Unwrap
With all vertices selected separate them out with P / Separate by all loose parts

cool, thank you

you can use Unwrap-Smart projection that can make UVs for multiple objects
select many object, enter edit mode of the last selected and this function will use all of the selected objects