Though I'm not entirely in love with this image I am in love with biro. It's cheap, it doesn't leak all over the page or in my bag or melt in my hand like other pens-especially fountain pens!
and most of all it can achieve shades and tones unlike other pens.
also its cheap...
So there is my little fan-girl promo on biro,
hopefully you too will pick up this humble pen and draw in your books and margins