To the point about the courier as a writing device, I use my iPad every day as a replacement for a legal pad.
I use Note Taker HD and after going through a number of styli(?) just got an
Ayl this past week. I've been using various capacitive pens for a year, but this one is absolutely perfect and only $11.
I'm a consultant and work with dozens of clients a month. Instead of going through cases of legal pads as I used to I now have everything sortable, searchable, storable and easily sendable (as email, .pdf, etc) in one program. It's fucking awesome.
Note Taker HD takes a little bit of time to get set up to where you want it; everyone is going to like different thicknesses and paper types and margins etc. but once you do it's freaking fantastic.