One of the Labors of Heracles involved a three-headed giant named Geryon (Γηρυών). I've never seen an explanation for this name, but at first glance it would seem to be connected to γηρύω "to sing" (participle γηρυών "singing").
Is there any connection between the mythological giant and singing? Otherwise, where did the name come from, if not from γηρύω?