i, too, have thought about it recently. something to mark a change. i even have a design in mind. and i'd put it on my upper arm - where it could be seen - but not all the time and not too big.
my wife and kids and boss and friends and co-workers would all be totally shocked. they would all think it was completely out of character. maybe that's a good reason to do it! like saying - you don't know as much about me as you think.
There’s a special providence in the fall of a sparrow. If it be now, ’tis not to come. If it be not to come, it will be now. If it be not now, yet it will come—the readiness is all. - Hamlet, Act 5, sc 2