Inflatable Seat Cushion
Inflatable travel seat cushions have numerous benefits. First, air is the touted by many as the ultimate sitting surface. Air gives, and when organized into indivicual cells like the Airhawk line of cushions, air slowly exchanges from cell to cell to even the pressure across your seat.
An inflatable travel cushion is also very portable and light making it a perfect choice for the airline traveler. Just a few puffs of air will fill these air cushions and a twist of the valve quickly deflates the cushion and then just roll it up and stuff it in your bag.