Excerpts from Alex Rozenshteyn's message of Fri Aug 13 14:11:11 -0600 2010:

> What if, for example, I want all windows of firefox on a specific workspace
> to tab together automatically, but no other tabs on that workspace?
>
> I guess I can see how to "add tabs to a layout" but I'm not sure what that
> actually means.
>

Take a look at XMonad.Layout.ComboP -- as I recall that's one of the
simplest to set up combination (sub layout) setups. It arranges windows
using properties of the window similar to manageHooks. This seems like
what you're asking for: e.g. className "Firefox" goes to left layout
which is tabbed, other windows go to right layout which is Foo.
--
wmw