Two years ago, I ran across this spiderweb table runner tutorial on The Crafty Cupboard, thought it was about the cutest, easiest thing I've EVER seen and whipped one up for our house. It is, by far, my favorite Halloween decoration.
I don't know about you all, but we do nearly all of our arts and crafts at the table, so I usually keep a piece of plastic over the table. Glue spills? No problem. Sharpie accident? No biggie. Yes, it's very 1950's housewife, but for now, it works. I promise it's the only piece of furniture in our house covered in plastic.
This project was very simple, it just took a bit of time and some very tiny, very sharp scissors.