Despite the fact that spiders are usually harmless and discourage other annoying bugs doesn't mean everyone wants them in their house. Spiderwebs are fire hazards and some spiders leave inflamed, pesky welts when they bite, even if they aren't of the poisonous variety. Toxic bug spray isn't the only answer. There are many natural options to repel spiders that are readily available in your home.
Doubts abound about how effective chestnuts or "conkers" are at repelling spiders. Apparently a spider will not build a nest in a chestnut tree, nor a building frame made of chestnut wood. Spiders taste with their feet, and the theory is that there is some sort of chemical in fresh chestnuts that repels spiders. There is also a lot of speculation regarding the types of chestnuts used. For example, sweet chestnuts are said to be more effective than horse chestnuts.
Another more pungent item that can be used to repel spiders is tobacco. Like chestnuts, nobody is quite sure why this works. Pipe or chewing tobacco is preferable for this process. You can put small bits of tobacco where spiders are troublesome, or soak the tobacco in water and spray or wipe the desired area. This remedy is even more effective when mixed with citrus juices.
Citrus scents are unpalatable to most insects, and lemon is among the most pungent and acidic. A few bits of fresh lemon peel, placed strategically in dark corners or on windowsills, will repel spiders as well as other more troublesome insects like mosquitoes. You can also repel spiders by regularly using a lemon-scented cleaner on your furniture and windows.
When all else fails, bring in your household predator. If you don't have a cat but really don't like spiders and other pests, a cat would definitely a good investment. Not only will your cat stalk and destroy any existing spiders, but the mere presence of the cat will keep them from coming back. Make sure that the spiders you are trying to repel are not poisonous, however, as you cat can get a serious injury from a bite.