Union edges

 From:  Andrei Samardac
6481.1 
Is it any way to union object but leav eges, especially after extrude? For example I want to union 2 cubes made by extrude but I need their eges to stay in geometry.

To do it I have to make: intersect, union, trim, join. May be some script for this?



Also just for fun, is it possible to make offset to produce those extra curves on sharp corners?

EDITED: 31 Jan 2014 by ANDREI SAMARDAC