Okay, this may not be the right spot for this type of question, but here goes: Is there a way to produce hard edges on models like in XSI, where you tag edges as 'hard edges' and when smoothing/subdividing, you can control the hardness of the tagged edges?
I know about chamfering the edges, but that's not the same as setting an edge to be 'hard' when subdividing. Anyone who has XSI should know what I'm talking about.
If what you mean is "how to have hard edges on a mesh when using mesh smooth or the integrated subdivision" then you only need to select the edge(s) you want to have hard and in the modifier panel change the crease value for those edges (up to one if you want them really hard) BTW, you also have this kind of control with vertices if you want (changing their weight in the same panel)
Another useful technic is using smoothing groups and materials. You can play with the smoothing groups of your base mesh and check "separate by smoothing groups in the mesh smooth panel" to have various smoothing groups separated by hard edges (you can do the same with materials)
I hope it helps,