If you want to build up on your muscle fitness but can't be bothered with the hassle of going to the gym just to queue for the weights machine, this is an excellent accessory to use at home.
This can be fitted to just about any door frame, provided the frame is not set flush against a wall, as the handlebars stick out a little. The contact points are padded, so you don't have to worry about your frame being damaged too badly.
For me, the best thing by far about the Powerbar is convenience, you don't have to make a mission to the gym every time you want to do your workout. It is versatile, you can use it for a variety of exercises including chin up pull ups, bicep pull ups and hanging ab raises. Although I don't use it for this, you can place it on the floor to do push ups as well.
Combined with an exercise mat (and imaginative use of normal home furniture), I plan to use this as part of a fully operational resistance training programme at home.