I had great results with the Terra ant baits. I got them from Home Depot. It was not something I put on cardboard, though. They were little plastic traps with the goo inside. You open one and leave it in the path of where you're seeing the ants and just leave it there. If you go back in an hour, you'll freak out at the number of ants streaming in and out of there, but in another few hours, there will be almost none. Leave it for another day or so and there won't be any. I used to have a problem with the sugar ants at our old house and I would put them in the kitchen or bathroom or playroom when I saw them and they took care of the problem. All the other tricks - vinegar, etc, never worked for me, just the Terra baits.