This is fascinating to me! Quantum computing is such an incredible frontier. But I suppose it will mostly be used to decrypt all the currently un-decryptable internet traffic being archived at the Utah Data Center [1]. But, maybe it will also be used for something good for humanity, too.
The cryptography uses are fairly boring in my opinion. We already have classical cryptography techniques which are not susceptible to quantum computers.
On the other hand, being finally able to fully simulate large molecules with significant quantum effects (not possible even on classical super computers) would be amazing.
[1] https://en.wikipedia.org/wiki/Utah_Data_Center