Antimatter gets used a lot in SciFi due to it's mind-bending energy density. If you can store it in a form that requires no power and is at least mildly idiot-proof then you've just solved half of your space-civilisation's energy problems. However, all of our current technologies have a drawback, either they require a power source1, they don't scale well2, have poor containment time3 or all of the above.
Now Carbon buckyballs are amazing things, they are quite stable, can be made with an arc welder and some pencils, they're not particularly toxic (unless you inhale a fine cloud of them) and they even "dissolve" in common hydrocarbons4.
Now, given that single ions have been trapped in Carbon buckyballs before... could we also store an antimatter ion inside one?
Lots of molecules have electric dipoles (which work a lot like magnets... just, without the magnets), if the buckyball was doped so that it had a couple dipoles on the inside pointing towards the single antimatter ion, could it be used to make a molecular Penning trap?
Note: Full-blown scientific realism is not a requirement, but it'd be nice if there was something that, on the surface, actually seemed plausible
 Aka. another point of failure, aka. the thing that converts the "off" switch into the "explode now" switch
 But at least we got the Eveready electric toothbrush out of it...
 Wherein you can fly to the stars... just not for long - Aka. Range Anxiety, but in space!
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