Wow! Lot's of good advice and suggestions here !! Thanks to everyone who posted!
I have an additional trick - I keep my small trampoline in my sewing room. I try to bounce 2 minutes every few hours, and it has really helped my neck, shoulders and lower back. It didn't help immediately, but over the last few months I have seen improvement. Along with regular breaks, stretching and moving around. Also, trying to remember good posture. :)