alt Hacker NewsOne theoretical use case is “Harvest Now, Decrypt Later” (HNDL) attacks, or “Store Now, Decrypt Later” (SNDL). If an oppressive regime saves encrypted messages now, they can decrypt later when QCs can break RSA and ECC.
It's a good reason to implement post-quantum cryptography.
Wasn't sure if you meant crypto (btc) or cryptography :)
I will never get used to ECC meaning "Error Correcting Code" or "Elliptic Curve Cryptography." That said, this isn't unique to quantum expectations. Faster classical computers or better classical techniques could make various problems easier in the future.