In all of Scandinavia the letter Y is a vowel, and I hear there is some controverse about whether it really should be classed as a consonant in English speaking countries.
>>the most consecutive consonants in a name ever<<
Scandinavian names can have four or even five: Of female names, Ingfrid, Hallfrid, Ragnfrid, and Arnbjørg come to mind. In Arnthrud you have five consonants, although at the time the name came into being, runes were used, and 'th' was written as one. In modern Icelandic the sound has its own letter, but this doesn't change the fact that it's spelled with five consonants today anywhere but in Iceland! Ingfrid can be spelled Yngfrid, but then, like I said, the letter Y is a vowel in Scandinavia... Of male names, these come to mind: Arngrim, Gunnbjørn, Hallfred, and Kollsvein. And, yes, all of these names are in use today.
Can't think of any first name consisting of only one letter, but in Scandinavian languages there are a couple of surnames (in case you're interested): Å (=river/brook), Ø and Ö (=island)...
Oh, and the Norwegian word with most consecutive consonants is 'angstskrik' (=scream of fear)! I shouldn't be surprised to hear that a frightened 1st time mother actually has tried to call her kid that, but has been given a firm 'no' from the authorities! :o)