Mmm, skittle system. Whereby you get your choice of the juicy rainbow depending on your skill and hard work... but who would distribute the juicy rainbow? Would they... redistribute the juicy rainbow!!!!!!!!!

No seriously. I can't think of any possible right now. A step back would be some barter system where you trade, but that's all capitalism is, money is just a more efficient way of doing this.

You'd need some advanced technology that made work basically unnecessary and where all basics for life are provided by this technology so none have to do or give up anything. Then perhaps it could simply be a desire to do stuff which drives any additional "economical" gains (though it seems it would not be looked at from that perspective at that point.)

But back to reality, I at least cannot think of a single alternative. It all seems just a different form or combination of either.

Well, with the bastardization of what Capitalism has become, the push has been for Free Markets.

Really, a truly Free Market system is a dream that can be shared with modern-day Marxists.

All of mine would require mass gene manipulation. Which is pretty objectionable stuff, so while an alternative..