1) Liederman Chest Press
This chest press is done by clasping the two hands together in front of the chest, palms together. Push your RIGHT hand to the left while strongly resisting with the LEFT hand. Then, reverse the motion by pushing your LEFT hand to the right, while resisting with the RIGHT hand. That is one rep. What you get is a bit of a sawing motion. Repeat 10 to 15 times.
2) One Armed Press Out
Place the RIGHT hand next to right pectoral, palm out. Now place the LEFT hand into right hand, palms together. Press straight out with the Right hand, resist with the LEFT. Pressing out should remain level with chest. Do between 8 to 15 reps, then repeat with the left hand.
3) Diagonal Press Downs
Place LEFT fist into right hand at about left shoulder height, left elbow will stick out and point slightly upward. Now, Press LEFT hand down at a diagonal so that you end the motion at your RIGHT hip. Repeat 8 to 15 times, then repeat with the RIGHT hand.
These exercises are great to add to any workout, especially if you are focusing on the chest. They will work your chest at new angles and with new motions than exercises with equipment. Give them a shot and let me know in the comments how they worked out for you.