These are the weapons of last resort, but some are solid and effective long term zombie killers. They are made up of whatever you can put your hands on at the time.
Hopefully you will always keep yourself well enough prepared to be able to destroy zombies without having to resort to any of these. Of course you may just be using them for fun. I hope not, that would be a little foolish and dangerous.
Effectively a simple club made of plastic and wires. Can be wielded one or two handed, or even swung from the cable. In my opinion a single handed approach is preferable, as it allows for a long arcing swing giving it a impressive first strike.
The problem is one of durability, a keyboard will rapidly come apart when used to kill zombies. If you are lucky you will be able to dispatch one or two zombies at most.
Only use in an emergency, and remember use the edge of the keyboard, not the flat.
A thrown projectile weapon made effective by their weight. Tins of gloss paint would have a similar result. As described by Tikiracer, they are best used from a great height.
I imagine if you were to use them in open battle against zombies you would need a very strong arm and hideously good aim. I would not recommend reaching for the ink tins as your first line of defence versus the undead, even if you have loads to spare. If you do, make sure they are full, otherwise they are useless.