Someone would have to write software for the Zoomer that spoke HP language or software for the HP that spoke Zoomer language. When I say "language" I don't mean anything special.. just that the devices would have to know how to interpret what was being sent. No such software yet exists for either device as far as I know.
<<< Can I program the Zoomer to act as a remote TV control? >>>
The IR port on the Zoomer doesn't have enough range to function as a remote. It's limited to about 2 feet in "short range" mode and about three feet in "long range" mode. Some folks have talked about developing an add-on piece of hardware to extend the range. I don't know if that's really being developed or if it was just talk.
<<< Is there anything I can use the IR port for besides talking to another Zoomer? >>>
I heard that Tandy was planning to offer an IR receiver for connection to a PC... but then removed the device from the market due to problems with the supplier. I'm not sure if any were actually sold.
So, the short answer to your questions is that right now, the only thing I know of that the IR is good for is "beaming" from Zoomer to Zoomer, but there are plenty of other things that the IR port *could* be used for.
Steve