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NASA invented wheels that never get punctured
(www.zmescience.com)
This is a most excellent place for technology news and articles.
Tubeless bicycle tires are often used with slime as otherwise they tend to leak from the edge of the rim as the pressure isn't usually high enough to create a perfect seal. That also means they are effectively "self-healing" and puncture proof. Also tires that have this strip of goopy glue like stuff on the inside that seals all by itself are starting to get rather common as well.