I have heard that Gold media, CDs and DVDs, have been making a comeback. These are gold-layered discs, (important) not just gold-colored. They use a different technology in the production which gives them a much longer life-span, 100-300 years, instead of the usual 1-5.
The better known brands are Kodak and Mitsui. They’re $2-3 each, less if you buy in bulk. The DVDs are about the same price as the CDs so obviously a better bargain if you have DVD-capability.
Here are a few links. The prices are changing as I write. You might also find them in earthly stores if you’re not living in the backwoods like me.
Delkin 25PK DVD $58.35
Verbatim UltraLife Gold Archival Grade DVD-R 4.7GB 8X, 50 pack $78.90
Memorex 4.7 GB Pro Gold Archival DVD-R (5-Pack) $21.46