Reading the shoulder injury thread and participating in some of the past exercise threads, I thought this might help some of you. I recently started taking the spice turmeric, along with black pepper (can increase absorption up to 2000%), and organic coconut oil. I mix them up and down it like a shot first thing in the morning. After just two weeks, my joints, including a nagging shoulder, feel better than they have in YEARS. Turmeric is a powerful anti-inflammatory and also is thought to have many antioxidant and possible preventative cancer effects.
Anyway, for anyone with joint pain, it's a cheap thing to try, it's helped me tremendously. I also recommend fish oil to those not already supplementing, but turmeric has really surprised me.
Disclaimer: always consult your physician first.