These names are plays on words to get gullible folks to say "My Cock's Small" or "My Cock's Long." Either one works on a fool.
*Mike Oxmall can also be spelled "Mike Oxsmall for more subtlety.
Chad: Oi mate, I changed my name to Mike Oxmall.
Bradley: Hi, Mike Oxmall.
Chad: You muppet.
Bradley: What?
Chad: Mike Oxmall/Mike Oxlong
A sunburn or suntan focused on the left arm. It is caused by the left side of the body being the only half that gets exposed to sunlight while driving. Presumably, it would be located on the right side of the body in countries where they drive on the left side of the road.