I've also have lower back pain and I use a rubber core ball that's around 22"-23" tall that I lay back on, basically I drape myself across it for a few minutes and do that a few times a day.

If my back is really bothering me then I use a polyurethane back belt when I'm standing for awhile.

The 3rd thing that works for short periods of time is Doan's back pills, they're a anti-inflammatory and pain pill