Just thought I would share this in case anyone is interested in a cheap, good workout tool for home use. I've been using an Xertube in our weight room at work and last night bought one for home use. It is for upper body... arms, chest, shoulders, back, neck and abs.
The link is to the manual for it, but you get the point.
I got my tube for $12.
Hint: I got the purple one for "extremely fit" because I first bought the red (moderately fit) one and opened it up and thought it was really wimpy.
So be cautious... however, I have been working out quite a bit for several months.
It comes with a door strap and sets of instructions for exercise.