Here's a really quick and easy DIY project that you can do last-minute to get ready for Halloween. All you need is some felt, tape, and a lamp.
Just start out by cutting your felt into a creepy hand/claw thing. I used my own hand as a guide, but made really jagged cuts so that it looked a little scarier. (I promise my hand doesn't actually look like this). Then take a couple of pieces of clear packing tape and cross them over the hand so that you can easily stick it to the inside of your lampshade. Then it can easily be removed after Halloween. Or you could just leave it if you like to be scared every time you turn your lamp on. Whatever.