If I wanted to add some extre feature to every application window
running, would I simply hook/subclass the Window proc of every such app?

Is this seen as inpolite or is it common practice? (I believe my mouse
manager hooks into just about every window I create).

How do I catch the creation of a new window so I may subclass it?

Doing this with many windows would require me to save and call the
original window proc's, is there a smart way of doing this rather than
simply placing them in some collection?

Thanks in advance,
/Casper

Well in case other ppl at a later time is gonna wonder the same
questions, here's what I found:

with the WH_CBT message filter specifier.

the issue at hand. Most system-wide hooks requires the callback to be
located in a .dll file.

HCBT_CREATEWND message and react upon it.

with, using the GetProp call. This works like a breeze.