Diatomaceous Earth
Organic bug killer. Safe for pets and kids. It shreds exoskeletons and makes the buggies dehydrate so they die. Used it in my old place and had tons of spider corpses *shudder*. Also works on fleas and ticks.
Your friendly, neighborhood horticulturist here...
DE is great stuff, with a couple of cautions.
Most important, because it is so microscopically (sp?) sharp, it will do the same thing to your lungs that it does to insects... shred them. So wear a mask, and pour it, rather than trying to spray it out, whenever you can.
That said, it is really good for soft bodied insects. Slugs in the garden, for instance, will crawl across a line of it and get their little tummies shredded, and dehydrate and die. That's what I use it for... poured on the ground around my hostas.
When I am trying to kill insects indoors, I always try to find a pheromone trap for the particular insect. They make them for spiders, I know. I use a different pheromone trap in my pantry to deal with meal moths that come home in boxes of stuff from the grocery store.
You can just google for pheromone trap and the kind of insect you have, and you will find lots of them.