[Asterisk-Users] How useful is the screen on IP phones?

[Jay Milk]

I know the compatibility of various IP phones (Cisco, Snom, Polycomm...)
has been discussed at length.  What I'd like to know is how useful the
"pixel-based" screens on some of those phones are.  Can I create
interactive applications, informative screens, feed still pictures (even
B/W), etc...?  I know *some* things can be done with an ADSI compliant
analog phone, and I'm guessing -- maybe incorrectly -- that the
expensive IP screenphones would allow even more functionality.

Things I'd be interested in:
- Advanced Telephony functions, such as: "shared" caller-id log among
phones within a group; Do-Not-Disturb with status-display; advanced call
routing w/o pickup (phone rings, send to voice-mail or cell-phone based
on keypress); presenting a list of voicemailboxes along with the message
count.
- Automation, such as: Display/control HVAC settings, security, lighting
(yes, I have the server-pieces in place for that, just looking to extend
the GUI)
- SMS
- Read email and/or alert to new email messages
- View instant messages and/or alert to instant messages

*IF* any IP phone is capable of such applications, which would be my
best bet?