It was done on palm via the IR port so I don't think it is possible on bb...
Posted from my CrackBerry at wapforums.crackberry.com
IR port is the magic word. IR (Infrared) is the communication most low-end and medium level A/V systems use for remote control. Since Blackberry doesn't have IR, then you can't take advantage of that.
If you are on a higher $$$ plain, and you are using ie: whole house control system like Crestron or AMX (to name a couple of the leaders in that field) that use touch panels for example to control everything from AV, Security systems, HVAC, Music & Video libraries etc. ie: for your mansion or estate one of the controls system manufacturers now support iPhone.
Back to planet earth... if you are using a Mac for your AV then I would imagine you can use iPhone and/or iPod touch to talk to your system.
Then back Blackberry... let's say you are using Microsofts Media Ctr. to control your AV and other stuff. Then in "theory" you could use you phone web browser to talk to your system.
All a bit of a pain in the ****.
Then back to the hi-end again. Those systems allow you to access your home from inside and outside. Connect to it via the internet, to view cameras etc. Or call your house before you get home to turn on the Driveway ice melter, heat up the home and send the elevator down to the garage.
Me, I'm in the business and I still have four remote controls on my coffee table I don't always practice what I preach