IIRC, a while back you posted about seating order in planes. In
Europe, it's quite common for the last 5 rows (back of the plane)
to be called, then when they have boarded, the next-to-last 5 rows
etc. This solves the problem of storing baggage, allows one to do
something better than waiting for boarding since one can estimate
when one's row will be called, and keeps the queue length down. And
it doesn't even need any fancy technology!