A Tunisian custom is to say, "This is how God split the Red Sea," and then break the middle matzah. 

Israelis of Yeminite origin wrap the afikomen in a napkin and place it over their shoulders throughout the chanting of the Haggadah, symbolizing both the liberation from Egypt, and more recently, the rescue of the Jews of Yemen in Operation Magic Carpet in 1948. 

haggadah Section: Yachatz
Source: Rabbi Zoe Klein