Personally I think it's nuts... but we have a number of secretary/admin/receptionist users with Cisco expansion modules
that have the shared lines of all of the people in their department on them. (i.e. a 7940/7960 plus the module). Usually
with some portion of the other lines set to just flash and not audibly ring. While I'd expect that in most cases they
really would be sufficient with busy lamp, sometimes they do use it to answer arbitrary calls for faculty that are out
of the office/etc.

With the transitioned cisco phones on FS/mod_skinny - it works the same way, however we're wanting to position ourselves
with suitable replacements, particularly for any departments that want more than bare bones functionality.

With the polycom phones, it appears to also work that way where you can have a sip account for every line key if you
want - even including the expansion modules.

However, on the Yealink phones (got looking at them cause of the T46G I won at ClueCon) we found the number of accounts
very limited.

It turns out that with the latest firmware (73.x) on the Yealink units the count is increased on a number of the models
(to 16 on the T46 for example). The problem is that with the middle tier ones that you'd add an expansion module to - it
doesn't really get you anything. If your base phone is limited to 6 accounts, adding the expansion module ONLY gets you
busy-lamp or speed dials.

We're working on getting the users "converted" to not using full lines wherever possible, but still want options open.

-- Nathan