It's sniping. I did it once a long time ago when I really wanted something - actually twice. Once I won and once I lost. There really isn't any danger that I can see. You put in your highest allowable bid and it will bid up to there. It seemed to do a good job of keeping it low. I think on the one I lost, it was at a bid higher than my high bid. I don't recall the website but I found it through googling.