Here are three less common surnames, this time from nicknames or occupations.
Calf was supposedly a nickname in English for a calf-like person (skittish maybe?), or perhaps for someone whose job was tending calves. Mary Calffe was buried at Bodmin in 1563 and the name was present from that point on in the Bodmin-Fowey district, spreading west as far as Probus and east to St Mellion by 1641.
Cogar was either a name for a builder of, or for a sailor of, cogs or cock-boats. It seems to have arisen on the Roseland and close enough to the coast for this meaning to be entirely credible. In 1545 John Coger was listed at St Michael Caerhays paying a benevolence (a land tax) and in 1588 Hugh Coga was buried in the same parish. In the mid-1600s the name was still largely confined to the Roseland, although by this time it was also found at St Ives and Gwithian in the west and on the Lizard. That could have been the result of migration from mid-Cornwall or perhaps denotes other, separate origins in the west.
Creeper is claimed to be a nickname, possibly from the English word cripple or from the word creep, as in crawl. It arrived late in Cornwall, not being recorded until Honor Creeper was buried at Tresmeer, to the west of Launceston, in 1689. The surname remained restricted almost entirely to the Launceston district in the early 1700s. Its late arrival combined with its geographical distribution make it unlikely that there was any connection with the Cornish name Creba/Crebo, found at Crantock, as I proposed in The Surnames of Cornwall.