Boric acid is used in some ROACH killers.
borax (Disodium Octaborate Tetrahydrate) is great for ants. its the active ingredient in Terro. Takes about a week to kill, but the ants take it back to the nest & it kills them all. works great for Argentine ants.
Homemade Ant Bait
16 tablespoons = 1 cup
2 cups = 1 pint
2 pints = 1 quart
3 teaspoons = 1 tablespoon
1 US fluid ounce = 2 US tablespoons
To kill colony:
optimum sugar to water concentration: 25%.
optimum borax concentration: 0.5 to 2%.
(NOTE: 4% borax repels or kills worker ants before they share it with the colony).
http://www.borite.com/new_construction.asp
http://www.bpbcorp.com/boratesht.html
http://www.manchestercitysch.org/centraloffice/MSDS/20%20Mule%20Team%20Borax%20Natural%20Laundry%20Booster%20-%20Dial%20Corp..pdf
Try cinnamon. I had ants coming in my A/C vent, and the cinnamon got rid of them. :)
Go to your fav big box store and get some large dish soap bottles. Pour them at the edge of your concrete and around your foundations. they will be gone in short order. I repeat about every few years. I have not had an ant in my house in what seams like forever.