fun fact about me:::
during my college days, I painted my room a navy blue so that I could use the walls/ceiling as chalkboards. Shortly after I left, the walls were repainted white even though I had washed off all my notes.
It wasn't that I was dedicated to getting good grades- I was dedicated towards understanding the world in which I lived in. I semi-intentionally personified it by turning my box of a room into a somewhat reflexive analogy of my perception. To this day- no matter what room I find myself in, I'm still in a box.
@lucifargundam
i don't paint my room dark to write on it.
But i do take notes for every single math or physics equation and scatter it arround my bedroom wall.
@lucifargundam thanks. But i'm more of a blackboard guy myself 
Mainly because whiteboards wouldn't be as white as you bought them after some time.
@deesapoetra
you could always go to your nearest discount store and buy a bunch of cheap white boards to thumbtack/tape on the walls :D
then you can have a writeable wall of white!!
Being in the US, there are stores like Lowes and HomeDepot that can provide large, thin-enough whiteboards for low-enough cost that if one wanted to- they could envelope themselves in a labyrinth of expo markings.