Graphing Boards on the Cheap

When I am tutoring a student working on graphing, I dread having to draw out the number line or the quadrants on my dry erase board.  Then I discovered something beautiful...sheet protectors.  I've learned from many other teachers that you can write on top of sheet protectors with a dry erase marker.
I found free graphing paper from PaperPrintOut.com.  All I did was print the graphing paper out on cardstock and slide into a sheet protector.  You can take it one step further and draw on the cardstock a number line (several of them) or x and y axis'.  So there you have it...graphing boards on the cheap.