Looking for ideas for stranger magic items

[Thomar_of_Uointer]

I'm working on a setting that leans more towards science fiction in themes, and that includes a change in the way magic items work. I was thinking something along the lines of Roadside Picnic (http://tvtropes.org/pmwiki/pmwiki.php/Literature/RoadsidePicnic), Darker Than Black (http://tvtropes.org/pmwiki/pmwiki.php/Anime/DarkerThanBlack), The Lost Room (http://tvtropes.org/pmwiki/pmwiki.php/Main/TheLostRoom), or the SCP Foundation (http://www.scp-wiki.net/). The basic premise is that there are many kinds of objects of alien or otherworldly (or unknown) origin, they don't really behave like anything a human would have designed, and have properties which seem random and vary in usefulness.

Since this category of science fiction focuses on how new discoveries change technology, I'm probably going to decide on some kind of commonly found object which is useful to society. One example could be small objects which radiate intense amounts of heat, leading to a steam-powered industrial revolution with these heating elements used as an infinite supply of power.

This means there would be two kinds of magic items (or "artifacts" or whatever they end up being called). One is an unmodified magic item in whatever alien or natural shape it was found in. The other kind would be a magic item that was created by modifying, harnessing, or repurposing another magic item (such as the above mentioned steam engines.)

I'd love anybody's ideas of specific magic items would work in this kind of setting (both modern and medieval). Can anyone share some ideas or point me to a good source for various objects players could encounter in this kind of setting?

Note: This was originally posted in World-Building but I didn't get any response there.

[Thomar_of_Uointer]

Here are a few I have so far:

Amethyst Bowl
This two-foot wide dish is carved from solid purple crystal.
If dropped or shattered its pieces will reassemble in a few seconds. If struck with an object made of pure silver, tin, or other metal it will make a clear ringing sound. If struck with steel, bronze, or an impure metal it will make a dull thunk. Fire makes the dish hum with a sound so loud it drowns out every noise for miles, but the direction of the sound cannot be determined.
Most interestingly, if the bowl is filled with water ripples will appear in response to nearby movement. The ripples are proportional to the distance and strength of the movement. A sparrow moving nearby would disturb the water as much as a horse-drawn cart a few blocks away. The ripples appear on the same side of the dish as the movement, so a careful observer can determine the direction the movement comes from.

Rusting Sword
This sword changes its appearance every time it strikes or cuts. It randomly ranges from the earliest ancient swords to the most modern, all in excellent conditions of repair. The sword rusts quickly after changing, in a matter of minutes. Any damage or rust on the sword disappears the next time it changes.