Cus D'Amato trained several champions and was an advocate of Peek A Boo boxing. the hands are in front with the boxer peeking over the gloves with the elbows tight to the sides. It taught a superior slip and dodge technique and allowed quick jabs and rights from any angle. Mike Tyson was taught the technique. I do not know of any books or videos out at present. I found a defination on Wikipedia and a narrative in Answers Yahoo.com.
Like many others I was skeptical of what I had heard, until I tried it. It is a superior technique but it is a dying form, because so many are not acquainted with it. One of D'Amatos students named Joey Hadley teaches it in his boxing gym and is planning on producing a training video of Peek A Boo boxing sometime in the future. From what I hear, his students are racking up in local fights using this form of boxing.