or have too much spare time when you...
take the time to cut a block of wood, glue some felt, and make your own white board eraser!
My board is metal so a self adhesive magnet for business cards was also added as the finishing touch.
btw, it's somehow gratifying to know that white boards use the same erasers as their darker predecessors
![Grin ;D](http://www.theshirtboard.com/Smileys/default/grin.gif)