I haven't climbed much over the last few years, but I still like to ride a slackline now and then.
I started my slackline experiences back in early 1980's during a summer of climbing in Yosemite.
The mind/body/spirit harmony created by slacklining is one that can be discovered relatively quickly, yet there is no end to the experiential discovery and learning as the years pass. No matter what style of slacklining you do, the moving meditation of this activity will certainly bring you into the focus of being “on”.
I wrote an article for www.slackline.com a few years back. It may still there, buried in their forum somewhere.