The Estonian ID card technology was originally imported from Finland; however, it appears Finns have for 10 years failed to come up with any significant e-services making use of them. So it is now agreed that Estonian X-Road solution would be expanding to Finland as well. From the article:
Sharing and joint development of X-Road solution is prescribed by cooperation memorandum, signed [on Dec 10] by Estonian and Finnish prime ministers. To our knowledge, this was the first international agreement in the world which was signed digitally.