These don't rely on The Internet or electricity. Changes can be made quickly, and on the fly, with a wooden-wrapped graphite device (not included). You can "load" yearly calendar updates for a very small fee, and it will keep track of all of your contacts. As of this time, e-mail send/receive is not an option but it does let you store a complete database of e-mail addresses, web site URLs, Twitter and Facebook accounts and more! Best of all, tests have shown that it will withstand a drop from a three-storey window AND being run over by a car!

[Link: filofaxusa.com]