I always liked the idea of an iPad, but though the device was too limited, for many of the reasons stated here, USB, proper file access etc.
I've also owned a Netbook, which was too small for serious use, and no touch screen.
I recently bought an Asus Eee Pad Transformer, with the keyboard dock. So I now have a decent 10.1 screen, I can carry it around like a Tablet, with 8 hours of active use, toucjh screen etc. So perfect for web browsing, checking emails etc. and instant on of course.
But also pop it into the dock, and so it essentially becomes a Netbook, with proper USB sockets, and also an additional 8 hours of usage (so 16 in total). It also closes properly, so it's not just a dock, but a real part of the device, so really is a Netbook in this mode.
The only real issue is lack of Tablet specific Android productivity apps atm. But this is coming, there are already several MS office compatible apps around, including one pre-installed for free. Open Office is on it's way. So this will eventually become a proper Netbook.
So far it gets used almost every day, my Laptop only gets booted up occasionally now to do my finances (in Open Office).