Japan and America

Japan has replaced China as America's largest foreign creditor. But I think it's the US government which holds more US government debt than anyone else, and similarly that the Japanese government owns most of its own debt. Japan and America are also together in not joining China's new development bank, the AIIB.

Greece

I haven't been paying attention to Greece. But now learn via Lubos that Greece may choose to start defaulting on debt payments to the IMF, less than a week from now. Also see: speech by Greek finance minister Yanis Varoufakis, made in mid-March. He mentions debt-deflation.