As more of a pain management measure, don't forget to ice it for 20 minutes 1-2 times a day depending on the amount of discomfort. It can really help.
Also, depending on the cause of your pain you can look into this Back on Track stuff. People have varying opinions on how well it works. I use one of the adjustable knee braces and like it because it gives a bit of support without hindering movement much, and it's pretty much invisible under clothes. Plus, I do think it sort of soothes my aches and twinges. Finally, it wasn't that expensive so I was willing to take a chance on it to see whether it could save me from some pain. >> Back on Track pain relief products horse saddle pads, equine products, blankets, leg wraps, boots, fir healing for pain relief
Honestly, the best thing for MY knee is to keep moving, but this can be different from person to person. Over the holidays I was on vacation visiting family and wasn't running around all over the place like I usually do... and what do you know, my knee starts flaring up and being grumpy. Since getting back into my active routine, it seems to be settling down again.