Yes, you can do it if you put the hash of a message INTO the chain as a transaction (I think they do something of this kind). But in this way you will share the limits of the Bitcoin network. They claim they do it in some efficient way, though. But I wouldn't trust it without checking their algorithm.

Anyway, any other "linear" blockchain (e.g. with PoS consensus) can do the same work. No wasting of resources is needed.