The nation of Israel, with its creation in 1948, would be a good example. The Zionist movement definitely used the unifying element of Judaism to bring its people together with the idea of the creation of a Jewish homeland; the Zionist movement had been a big nationalist movement for years and years (since the 1800s) before Israel was ever created.
If you look at the Middle East, you can see that Islam is being used to create some sort of nationalism. The various countries of the Middle East are trying to use their identity as Muslims to bind themselves together (given that they often have different ethnic groups within them) and to distinguish themselves from others. This is made a bit more difficult by the splits within Islam (Sunni-Shi'a).