Here's my latest creation.
A business card-sized B/X character sheet card. They measure just 85x55mm, yet still have room for the essential character details. I originally designed these as an extra item for an Oubliette PDF, but always intended to get some printed up. They have been professionally printed on sturdy matt card. You can buy them (£1.90 for a pack of 50) from my webstore: http://squarehex.myshopify.com/collections/role-playing-games/products/b-x-mini-character-sheets
As an added bonus all orders placed by 31st December can enjoy a 10% discount by adding the code: kick5 at the checkout.
You'll also find the rest of my character sheet pads on there.