Domestic rugby in New Zealand has a pretty cool thing as well, called the Ranfurly Shield, which I got reminded of because the stupid "NBA Cup" is just repackaged regular season games with only the final being an extra game they wouldn't otherwise just be playing anyway.
I'll spare you all the exact details but after being initially awarded to undefeated Auckland in 1902, it's basically just a challenge cup - all home matches played by the holders (except for playoff games) are shield defenses. The away team has to win the match to take it; a home victory (or a draw, although those aren't too common in rugby) results in the shield being retained by the holders. Those are normally just league matches that the team would otherwise be playing anyway. Since there are two levels of provincial rugby these days, the holders are required to play teams in the other level (in practice always held by a team in the top level, so they schedule matches against teams from the lower level that they never lose) to give them a chance to contest it. There's a little more to it than that, but I did say I'd spare you on those details because otherwise I have a penchant for long-winded rambling with going off on tangents.
It does have some prestige attached to it due to having such a long history, but I don't think you'll find very many people saying of the shield holders, "hey look, it's the best provincial rugby team in New Zealand!" Still a cool thing to have going for bragging rights though.
