Before deciding on one of these, read Insects and Spiders 101 for an idea of the factors you should consider before choosing one of these pets. Some of these may be illegal where you live, so you need to check into your local laws as well.
Ant farms are an interesting way to have keep insects in the home. Easy to keep and fascinating to watch, ants are truly low maintenance pets. Just don't let them escape! The easiest way to obtain ants and start a colony is by purchasing a commercial ant farm.
Tarantulas have been popular as pets for quite some time now. Tarantulas are venomous, but many species produce no more of a reaction in people than a bee sting. The degree of reaction will vary with the species, the person, and the amount of venom injected. There is a danger of having an allergic reaction to the venom however, including anaphylactic shock. Beginners should seek out a well known, docile, safe species from a reputable source. There are several hundred species of tarantula, and some are more aggressive than others, and a potential owner must be sure of what they are getting. A reputable breeder or source will help a person decide on an appropriate species and educate them on proper care and handling. Owners must be aware of the potential dangers and liabilities of owning a venomous pet. Care is definitely required when handling tarantulas, as much for the protection of the spider as the owner - even a short fall can be injurious and tarantulas can be quite skittish.More information: Tarantulas as Pets
Stick and Leaf Insects
This group of insects is large and remarkable - relying on camouflage as a defense mechanism, most of these "phasmids" look like sticks, twigs, or leaves. The keeping of stick insects has been popular for many years in the UK and other parts of Europe. As a rule, these insects are fairly easy to care for, reproduce well in captivity, and are fascinating to watch. While they can be handled a bit they are extrememly fragile. In some parts of the world, they are considered possible agricultural pests so importing foreign species may be forbidden. More inforamtion: Care of Stick Insects
Growing in popularity despite the bad reputation that cockroaches are given. These guys are about 2 inches long and are pretty sturdy, so unlike a lot of other invertebrates they are quite easy to handle. They are also very easy to care for and are one of the most low maintenance pets available. More information: Hissing Cockroaches as Pets
Like tarantulas, there are many species available and the stength of the venom varies between species. While some species are highly venomous, the most commonly found pet species, the emperor scorpion, has a venom that has been likened to that of a bee or wasp (but also like with a bee sting, a deadly anaphylactic reaction to scorpion venom is a possibility). Emperor scorpions are a striking blackish color and are an impressive 6 inches in length when fully grown. Scorpions are also not great for handling, but they are also not all that difficult to care for. More information: Emperor Scorpions
African Giant Millipedes
While they don't have a thousand legs (they have up to about 400) these millipedes are pretty amazing, reaching a lenght of about 10 inches. Several species can be found and most are a dark brown or black color. They do secrete a mild toxin from pores on the body, but as long as you wash your hands after handlingjthem it is rarely a problem (some people are more sensitive than others to irritation from this toxin). They are also not very difficult to care for and can be kept in groups. More information: Keeping African Giant Millipedes
Also known as doodlebugs, antlions are the larval form of a flying insect. However, they stay in the larval form for 2-3 years, and this an interesting stage. Antlions construct a cone shaped pit in sand, and lie in wait at the bottom for an ant to fall into their pit. They are not very active, but it is interesting to watch them hunt. Kits can be bought for keeping Antlions. More information: Antlions as Pets
These are exotic and graceful looking insects that are relatively easy to keep as long as you can keep supplying them with insects to eat. They require a fairly warm habitat and high humidity level, and a steady supply of live insects to hunt for food. More information: G.J.L. Ramels Care of Mantids page.