Doctor Who: Time Traveller's Diary BBC Children's Books Penguin — Random House

Whether you're sight-seeing in the constellation of Kasterborous or slumming it on planet Earth, you need to be able keep track of things - especially if you're a time traveller. This handy Time Lord-approved diary is perpetual, so will work whichever year you land in, and with a day to a page there's plenty of room to record your adventures or plan your next move.

It's also packed with useful information about holidays and anniversaries from all over the galaxy, from New Year's Day (1st January) to the Second Manifestation of Kroll (12th December 2528.) There's even a section of Useful Information, including international dialling codes, conversion tables for weights and measures, quantum mechanical equations, and how to tell a Silurian from a Sea Devil.