PocketMod

Digital is so last year, what you need is a bit of paper tucked in your back pocket, one that you can change without powering up, one that won't cost you more than a couple of pence, and will keep all the numbers of the local takeaways available in a flash. Make yourself a pocketmod. I saw this in ready made mag and thought it would be quite useful. You can make your own custom version and even download a little desktop app for Mac and PC.