Fergus mac Roich was the namesake for a (gelded!) racehorse of the same name. Fergie loved to fight, but this gelding's sire was named Peace Rules! 

Fergie's immortalized in song in the awesomely-named band The Lord Weird Slough Feg's song "Fergus mac Roich."

Fergus's descendants gave their really long name to Cormromoe, in Ireland's County Clare.

Big Man F's name means "Manly Strength, the son of Big Horse." Who knew a name could be so flattering?