IGN 1:1m roamers
Go to www.sahara.../news
or .../maps to download a .doc file (120k) with 8 roamers for the IGN 1:1m maps covering the Sahara.
Each roamer is a grid covering one square degree of an IGN one million map and is calibrated at 5 minute intervals. Once printed off on acetate (aka, clear transparencies for overhead projectors), it's a less error-prone method of reading a grid reference from a map than with a ruler and pencil.
Thanks to Terry Davies for producing them.
Author of Sahara Overland and the Adventure Motorcycling Handbook, among other things