Primecoin was the first coin to introduce a prime number sequence for mining. It has a lot of cool features and it has a good roadmap.
Unfortunately, the coin's price has been decreasing, and I guess it is currently way undervalued.
It is indeed one of a kind but that may not be enough. Why would a merchant care about prime numbers? Ultimately people have to use a coin in order for it to be useful. If the only purpose is dealing with prime numbers usage will never be widespread.
fair enough but at least it's a step up over Bitcoin in the mining electricity wasting issue.
and i think it does still function as a currency like most any coin with a wallet etc.
but just think of how much power is burned with all that Bitcoin mining hardware out there.
then take something like XPM and think well that power can be put to some good use..
coins like Prime Coin or Grid Coin etc have my blessing.
they may not be perfect but at least they are moving in a positive direction.