Well, we have Sicily, England, and Antioch as areas ruled by Normans (Note that the 'Norman Kingdom' wasn't in any of their titles, just something I use to differentiate that period of Sicilian rule from others). If Sicily survives instead of being subsumed into the H.R.E., it could have done magnificent things. Some other possibilities:
1) Richard Curthose gets the Kingdom of Jerusalem.
2) A Norman lord inherits France (not too implausible)
3) A band of Norman adventurers strikes off into Al-Andalus in the same manner as they did in Sicily. Very interesting results arrise.
4) Robert Guiscard succeeds in making himself Byzantine Emperor.
5) IIRC there was a Norman polity in Anatolia at some point. I shall have to check.