We construct a non-locality game that can be won with certainty by a quantum strategy using log n shared EPR-pairs, while any classical strategy has winning probability at most 1/2+O(log n/sqrt{n}). This improves upon a recent result of Junge et al. in a number of ways.
@article{arxiv.1007.2359,
title = {Better Non-Local Games from Hidden Matching},
author = {Harry Buhrman and Giannicola Scarpa and Ronald de Wolf},
journal= {arXiv preprint arXiv:1007.2359},
year = {2010}
}