There seem to be different views on where the saying to tie the knot comes from. At one of our recent wedding ceremony, the Priest had the Bride and Groom hold hands as she wrapped a sash around their hands (tying the knot) and pronounced them Husband and Wife.
I like this tie the knot ring from Rony Tennenbaum. He has a number of different collections with unique designs for those looking for something a little different.
Image via Hudson Grove