Instructables has a very nice key holder/thing made from a bicycle multi-tool. It doesn't have the nice Leatherman pliers but personally I prefer it. http://www.instructables.com/id/Friendly-Folding-Keychain/

It's amusing. I work at a British research establishment that used to do work for the Royal Navy. We had a little set of toy train tracks set up in the garden to help with our work on missile targeting systems.

I've been using a Logitech wireless trackball for a while and it's just fine for me, but I'd probably still recommend Bluetooth. We had an incident at work recently where a new WiFi network took up a huge proportion of the available 2.4ghz spectrum and killed the mouse we used for seminars stone dead. Bluetooth has more advanced signal processing and we've replaced the old mouse with one of those.

My personal emergency PC is a Sony Vaio C1 Picturebook. The VFK model with bluetooth. 650Mhz, 128mb of RAM (upgradable to 192mb) and a standard, easily replaceable 2.5" ide hard disk. Not the speediest machine in the world but I gave it a bit of a kick by installing Xubuntu. The only downside I'd say is the size of the screen. At 1024x480 I sometimes have trouble fitting entire dialog boxes onto the sceen. However I think there's a better version... Possibly the C1M, that had an 800Mhz processor, 256Mb of RAM and a 1280x800 resolution screen. The size of a hardback book, I'd heartily recommend it.