Controlling indoor pest problems without the use of poisonous sprays and traps is beneficial for a variety of reasons.  Not only do you prevent these noxious substances from entering the environment, you also remove harmful chemicals from your home, thus eliminating the chance that you, your children or your pets will be harmed by them.  There are as many pest solutions as there are types of pests, but here are a few tried and true methods.

For fruit flies: These insects are particularly attracted to wine and beer, so if you leave some of either out in a dish, they will flock to it and drink until they die.  Alternately, you can leave an inch of wine at the bottom of a bottle and cover the opening with plastic wrap.  Poke holes in the plastic large enough for the flies and they will enter but will not be able to figure out how to leave.

For cockroaches:  Cockroaches, along with a variety of other insects, mites and fungi, are deterred by the presence of Neem oil, which can be purchased at most plant nurseries.  The oil can be applied to anywhere insects are observed, and especially along floorboards and the backs of cabinets, where cockroaches tend to linger.

For flies, moths and other winged pests: These insects are deterred by the scent of cloves and sliced cucumbers, so place these in any problem areas.  These insect populations can also be controlled with Neem oil.

For mice and rats: Pure peppermint oil repels small rodents, as the smell is too overpowering for their sensitive noses.  Spread the oil along floorboard and in the backs of cabinets.  You can also use non-lethal traps to catch these critters and so that you to release them back into the wild.

For ants: Diatomaceous earth, which is used in gardening and pool maintenance, kills ants upon direct contact.  Place some in the path of any ant trails you observe, and outside any openings that ants are coming through.

If your insect problem is too widespread to be controlled without professional assistance, look for a company that does natural fumigation with carbon dioxide, or another organic method.  For instance, some termite companies only use orange oil in their treatments.  Check this website for a list of environmentally friendly pest control services.