Comment Re:Enjoy it while it floats (Score 4, Informative) 66
When underground radioactive elements decay, helium is a byproduct (look up "alpha particle radiation"). Because it's a noble gas and doesn't bond with anything, it seeps its way to the surface, where it escapes into the upper atmosphere. Some helium can instead become trapped by non-porous rock, in underground pockets. Those same pockets sometimes have natural gas deposits.
So you find a natural gas deposit, tap it, and what comes out as well? Helium. It's not the main product they're after when they go drilling, but it is valuable enough to set aside and sell.