Tai Chi has been a great experience for me as well. I think because of its strengthening and stretching, balance and control as well as low risk of putting me out of work with an injury. It has been awesome for my lower back. 
    It can be very calming and has a spiritual side which you can explore if that's your thing. Tai Chi contains the roots of all other chinese martial arts so you could use it as a stepping stone off the couch. 
    I personally hope more people will find and benefit from Tai Chi. 

"It's like Yoga without having to roll around on the floor :)" - me