Yeah I imagine the current system took a while to design and code and takes quite a bit of processing power on the computer front due to how it responds.
I can see how a similar project would work with an arduino but it depends on what compromises you're prepared to make on what it does.
I have a few ideas. I'll send you a PM and then we can communicate about it via email (and/or instant messaging of some kind at some point).
For anyone else reading - this doesn't mean I'm going to undertake the project so if anyone else would like to step in - be my guest.
Mowcius