Fellow T-mutants ,
One of the best part of working out at home (other than you control the music and no one gets in your way) is that you can get creative with your equiptment. I've come up with a cheap and great way to work you grip and pack the beef on your back - Tennis Ball Pull-ups. This will cost you less than $12 and it is worth every penny.
This is what you're going to need: Two 2ft pieces of rope (get rope rated for at least 300lbs), two 3/8" steel washers, duck tape, steel shot (bee bees work fine), two tennis balls, and two hooks (rated for at least 150lbs each).
Let's get started. One hole in the top of the tennis ball and one at the bottom of the ball. Make one hole as small as you can to get the rope through. The other one can be as big as you like. Pass one of the pieces of rope through the tennis ball. You will probably need pliers to pull the rope through. Feed one of the washers through the rope up to the tennis ball and tie a knot in the rope