Bluetooth is great for bluetooth-enabled mobile phones and PDAs. I haven’t used a PDA in years.
With my Sony Ericsson T610, I can:
sync my contacts and calendar
see caller ID on screen
remote control iTunes, DVD Player, Powerpoint, or just about any app
mute iTunes when the phone is in use
Those last 3 are possible with Salling Clicker. I also archive my SMS messages to BluePhoneElite. Not that I ever look at them.
If you want Bluetooth, I think a trip to HK is in order.
512m of RAM isn’t really enough if you’re doing a lot of work. Final Cut Express/Pro or iMovie would do better with more. A gig stick to bring your iBook to 1.25 gigs would only set you back around 5k.
Have you considered a PowerBook? You’ll need a lot of space for video editing. You could use an external drive but it’s nice to carry the move with you. I think you’ll need around 12 gigs per hour of DV.
Lots of stores can upgrade the iBook HD. But why not just get a PowerBook. You can plug in an external monitor and get tons of screen space for Final Cut.