Curious Devil Chime

Indestructible artifact. Once rang intentionally by someone a demonic portal opens up right next to the ringer and a massive demonic head appears, screaming, "Soon, you're soul shall be mine! Ten!"

And then it disappears.

If progressively rang intentionally by the same ringer, regardless of the time elapsed, the demon's head will appear & repeat the message above, but continue the countdown to zero. At reaching zero the ringer is slain instantly, stripped of his soul, and dragged to hell. (No save).

The Glass Watermelon, with Ghost Piranha inside

Fragile artifact. A beautiful watermelon made from blown glass, partially transparent. Inside what looks to be a fish with a weirdly set jaw swims inside. That's all, it's just pretty.

If anyone breaks the glass the fish falls out flopping onto the next immediate non-organic surface, and continues to flop about gasping for breath. Anyone touching the fish is automatically bitten for 1 HP damage and discovers that the fish is intangible. The fish is a ghost piranha whose locus is now rooted to wherever the glass watermelon broke. Only removable by exorcism.

Puma Pants Alarm

Enchanted britches made from the skin of a mountain lion that can ensorcel a given 20'x20' space around the user, often a room. Casting time is 1 minute as the caster goes about the 20'x20' space, touch and declare what is his by saying, "This is Mine." Up to ten objects can be alarmed for the next 8 hours in this manner.

Anyone, including the caster, who attempts to leave that space with said items will shit themselves immediately. (No save).

Mirror of All Angles - When viewing yourself in in this full-length mirror you can issue the following commands: back, overhead, beneath, ideal light, bad light, flaw, fat, thin, dead.

"Back" will show you your own back in the reflection.

"Overhead" will show what you look like from a close bird's eye view.

"Beneath" will show what you look like seen from under a glass floor.

"Ideal light" will show what you look like in a room with flattering light.

"Bad light" will show what you look like in unflattering light.

"flaw" will show a zoom in on whatever is the greatest flaw in your appearance that can actually be fixed.

"Fat" will show you fatter.

"Thin" will show you thinner.

"Dead" will show you as a corpse in advanced decomposition. Due to a glitch in the magic it will also kill you.

Shears of Forever - This pair of scissors seems to reflect the vastness of the cosmos in their metal surfaces. If they are used to cut a hair off of a creature's body, that hair will never grow back again.

Somewhere on another plane of existence there is a small planetoid covered in all the hair that the shears have ever cut. The hair sprouts from the fleshy surface of the planetoid and continues to grow forever, so at this point it is covered in tangled layers of hair several miles deep. Anyone in possession of the shears can teleport to this planetoid by using its sharp edge to cut a trap door into the floor of an establishment that has served as a barber shop for at least a month.

Who knows what wonders have been lost in the miles of hair?

Journal of Obsessive Documentation - This is a pale, thin, softcover book with a cartoonish depiction of a scribe on its cover.

The journal has infinite pages but will only accept diary-style writing, with clearly dated entries and personal recollections. It will also only take one entry per person per day. For every 99 individual entries a person racks up, they can write a fanciful 100th entry of how they "wish" the day had gone or will go for them, and within reason it will magically come true (this is equivalent in power to how a Wish spell works).

However, there is a chance that anyone who submits a 100th entry will become obsessed with keeping their "secret diary" away from prying eyes and will waste future Wishes on arranging absurd levels of security for their journal.

Sword Of Knightly Glass

A longsword made of glass, this is an ineffective weapon and purely ceremonial in nature. It is surprisingly sturdy, but not unbreakable.

Once per day, it can be used on a humanoid loyal to the wielder, by tapping him/her with the flat of the blade on each shoulder.

If the humanoid is lower than 4th level /4 hit dice, he will immediately gain the powers of a 4th level fighter in all respects, except that he will have a maximum of 1 hit point. This effect lasts the rest of the day.

On a related note. I was doing a quick personal list of common magic items in 5e and yeesh there more or less arent any. Just 3 out of the whole list.
Potion of Climbing, Potion of Healing, and Scrolls with cantrips or 1st level spells.

So simple chore-saving magic items would fit well to fill in the gap.

THE MISCELLANEOUS COMPENDIUM OF ITEMS MADE PURELY TO WIN BETS

Whistle Of Cat Herding

A military whistle with a couple of decorative feathers. When blown, it summons all felines in a 90-foot radius, who converge upon the user and assemble themselves in military rank and file. They can then be commanded to march in any direction for up to 120 feet. They will do so in perfect synchronicity.

Ixion's Indiscriminate Bib

When worn, any one thing the wearer eats during the course of a day will taste like strawberries.

Dwarvish Metadice

Once a day, this pair of six-sided gaming dice can be telepathically commanded to come up with the exact result the user wishes, provided that it is in a game or decision with actual stakes greater than 20 gp value.

The catch is, the player of the character must then accept that same result for his next two in-game dice rolls wherein such a result is possible (i.e. no 12s for a d4 roll).

Lens of the Moral Guardian - A magnifying glass whose frame is topped by a stern looking eyebrow. Anyone observed through it glows bright red if they have fornicated in the past 24 hours.

Chamber of Red Rage - This is a room that is a most unpleasant shade of neon red. Anyone who spends more than a few minutes in it gradually grows more irritable (depending on their willpower). Within a few hours they are ready to kill at the slightest provocation. The rage clears away completely upon exiting.

This is a particularly cruel and amusing way of disposing of unwanted prisoners. Just put them in there with their best friend or romantic partner and enjoy the show.

Bannister of Upward Sliding - This is a smoothly varnished staircase bannister. Sit on it and tap it thrice with your hand and you will magically slide up it at a safe speed. Watch out though, tap it four times and you'll slide up at the speed you would slide down!

Water Degravitator - This tool looks like an ice-cream scoop with a bowl the size of a grapefruit. If you use it to scoop up water and flick your wrist -just right- the water is no longer affected by gravity for the next five minutes and drifts about like a bubble. If you practice the wrist flick you can set this bubble in mid-air or send it careening in any direction at any thrown speed.

Multi-size Invisible Cube - This invisible cube is as light as dove but as sturdy as steel. Its surface is easy to wash of dirt and other substances that reveal it. It is normally three inches across, but there are special holes in two of the corners that allow someone to hook their fingers into it and pull until the cube stretches to a maximum size of five feet. It can be squeezed back down again in the same manner.

Feline Wings - This harness is equipped with a pair of cherubic wings. When attached to a house cat, and only a house cat, it allows the wearer to fly with all the speed and grace of a slightly overweight hawk. The harness grants an instinctive understanding of flight to the wearer.