Wooden gymnastic rings for dips, pullups, and other skill based work. Plus you can take them with you when you travel!

http://www.amazon.com/Wooden-Gymnastic-Rings-Gymnastics-Crossfit/dp/B005CVGCJK/ref=sr_1_1?ie=UTF8&qid=1372447874&sr=8-1&keywords=wooden+gymnastic+rings