Weight vests are an amazing way to increase resistance in your strength and conditioning workouts. If you are working out at home, these vests can add weight to your bodyweight exercises. A weight vest is a bit more comfortable than sticking weights in a backpack and the weight is evenly distributed which works great for pull ups and push ups. These are great if you do ring/gymnastic style training or rosstraining type workouts. The vest is also good for running, and since it is waterproof, can even be used for swimming workouts.
The Xvest is one of the most popular choices and is usually regarded as the best you can buy. However the great quality can be a bit expensive. Shown is the 20 lb version, it comes with twenty 1 lb. weights and you can add them as you wish. Xvest also makes vests that can take more weight for more advanced users.