err...you'll probably always be able to buy from specialist online retailers.
Sure, mainstream shops have almost entirely stopped selling tape stuff, but who needs real shops.
Shop online, I have no doubts that in the year 2050, if you wanna buy a few mag' tapes for your ancient museum piece/antique...you'd be quite able to.
There will be millions of those VCRs circulating for decades to come...they'll probably remain cheap too.
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As an aside...
by Dec 2006..a company is planning on selling a disc reader/writer than can cram anything from 300 to 1.6 Terabytes of data on a DVD sized disc.
Forget blu-ray and HD-dvd. Its possible that holographic disc will take over as the eventual global format for movies.
see :
http://www.inphase-technologies.com
Calrissian: 0100110