i don't have any terro in my house, right now--but it used to be made with arsenic! check the list of ingredients before you set it around. i can't vouch for it, right now--maybe they've changed the formulation. it used to be fatal for pets.

http://www.mom4real.com/homemade-ant-killer/

Found this too...

My DIL (in North Carolina) uses Borax and powdered sugar combo. I've seen it work.

I have used soda water on the mounds and it worked good...

I understand it works but you have to mix it with something that attracts them, like sugar. They won't eat it by itself (I tried). I am also reluctant to attract more than I already have...

I admit I used Terro liquid bait traps to FINALLY get rid of mine. It took about 3 series of baiting but the trick seems to be done. Except for the occasional outbreak of tiny tiny sugar ants - not nearly as prolonged or invasive as the Argentinian ants I usually battle - they seem to be gone for good. The baits will attract them, so be prepared - you have to just ignore them. I set the baits out before DH and I left for a 3-day business conference. When I came home, the only sign that there'd been activity was dead ants in the traps. That was February and I haven't had any trouble since.

Just as an aside - I use ammonia to kill bugs. They die quickly, dry up and are then easy to vacuum up. That's usually what I do if I find ant lines, until I can put out the bait.

For spiders, spray the areas they like with vinegar about once a week. They don't like it.

I am going to try cinnamon if they invade my apt again. The apt complex does have a service that sprays but I would rather have them spray outside then in this apt that doesn't have very good cross ventilation.

I use plain vinegar and it works just fine. I had done a Google search for "safe" methods of getting rid of ants. I don't know if it kills them or chases them, but they go away and stay away. Vinegar also kills the weeds in the cracks of sidewalks. Just don't spray it on your flowers.