yes, and no.
The Z does indeed support usb wifi.
unfortunately the Z's usb doesn't quite have the juice to power the external usb radios.
So, if you wish to use a usb wifi setup, you'll neet to use a powered hub.
I think there are internal wifi hardware hacks for the 1000, but I suspect they are tricky and dangerous to the Z.
If you are thinking about storage on your 1000, 4 gig sd cards are now pretty affordable, and can run on sharp, cacko, OZ, pdaXrom beta 1.1. All besides OZ require you to insatall an sd driver ipk to make it work, and my experience in sharp, at least, is that the card needs to be partitioned.