Chess algorithms are usually tuned to the targeted hardware and use various 'tricks' (like using 64-bit board representations that can be managed and operated on easily by 64-bit procesors). Having ranks of processors could allow new algorithms to emerge that might identify ways to use very massive processor banks for a variety of algorithms: physical systems that are currently difficult to model (EM fields, turbulent fluid flow, large molecule interactions, encryption/decryption, etc.)
On practical advantage is a better understanding of how to break algorithms into pieces that can be efficiently executed on a large number of processors. Chess computers uses algorithms that are common to other difficult problems (economics, scheduling, FPGA routing, etc) so this could help identify some new algorithmic approaches to solving other problems.
While it's certainly interesting to speculate on the potential applications, I'm reminded of similar questions about the neverending increase in disk storage capacity. It seems like a case of "build it and they [applications] will come."
I'd like to see stacks of these implement a distributed chess playing algorithm to create the best chess playing computer in the world. It would crush every existing chess computer out ther. After we do that we would move on to predicting the weather...
Source synchronous LVDS -- that would be great for a robust, versitile interface. 8 data lanes is not too many pins compared to the much lower bandwidth parallel interfaces we have used to communicate with processors currently available on the market. Thanks for the information! I hope to have the opportunity to use the Parallella.