$IONQ Inc.(IONQ)$  

IonQ offers something relatively rare in public markets: direct exposure to the emerging quantum-computing industry.

If quantum computers eventually solve commercially important problems that conventional computers struggle with, the addressable opportunity could become enormous across areas such as pharmaceuticals, materials science, optimisation and cybersecurity.

But this is still an emerging technology. Investors are valuing IonQ largely on what the company could become rather than today's earnings, making the stock particularly sensitive to expectations.

Overall: IONQ is unquestionably speculative, but that's part of its appeal. If quantum computing develops into a major computing platform and IonQ establishes itself among the winners, today's opportunity could ultimately prove very significant.