I have a ton of chronic pain. In my upper back (thoracic area), my shoulders, my lumbar area, my hips and my legs. Practically all my body hurts many days.
I have used tennis balls and lacrosse balls to release some trigger points, and have used foam rollers in the past. I have used high density foam that is pretty hard (and it hurts!) along with foam rollers that are not as dense, and softer. They didn't seem to do as much for me.
So then I got this one:
This is the Muscle Mauler Max, and it is pretty cool. It offers deep tissue massage and trigger point release for many areas of your body. It isn't too hard, has some flexion to it, but it isn't too soft either. I like that it has a hollow inside, and while it is sturdy, it seems to release the muscle tension without too much pain.
When you buy it, you also get an instruction sheet and a free eBook that shows some of the things you can use it for, such as your hamstrings, upper back (thoracic spine), IT band (my sore spot!), your lats, glutes, hip flexors, calves and lower back.
If you have any issues with any of these areas on your body, you have to try this.