I don't know of anything like that either. Small fuel cells rely on expensive precious metal catalysts and large ones have too much capacity to be a good match for the distributed generation sector.

A technology that is commercially available but too expensive at present for large scale adoption, like fuel cells, is more mature than a technology that hasn't been demonstrated even in a cost-is-no-object context. That's why it's strange to hear fuel cells described as even further out than fusion power.