you know that seemingly useless, outdated book that randomly shows up at your doorstep periodically? that's right - the phonebook. well, try teaching that old dog a new trick before you kick it to [recycling on] the curb next time.
if these brick-like books are good enough as a makeshift booster seat for a little one, they can certainly ass-ist you in your meditation practice, giving you a firm cushion under your cushion for a better, more comfortable posture.
need more lift? just add another one to the stack.
to really transform your phonebook(s) into a meditation seat, place it inside a pillow case [you know, the one you still have that lost its mate to the sock monster ages ago...].