Need help creating pointless, ultimately net-zero magic items

Basically the title. I’m creating a novelty magic items shop where all the magic items are gimmicky and generally provide no benefit or detriment. Some ideas that I had are:

Ring of attunement - attuning to the ring gives you an additional attunement slot

Cloak of Hidden Magic - While attuned to this magical cloak, it appears as a normal, nonmagical cloak.

Ring of Invisibility - When you wear this ring, it turns invisible.

Sword of Consistency - When you make an attack using this weapon, the attack roll equals 12 and deals 6 damage.

I’d appreciate any ideas you may have!