You need to check out "The Rat Bike Zone"
Its mostly motorcycles... but there are a few peds in there too.
Go to "gallery' for some unusual creations... by the way..most of their owners consider their stuff to be a form of rolling mechanical sculpture.
mechanical skills, and
welding and fabricating skills
and if you want to get fancy..
then it also requires bodywork (fiberglas and bondo)
the ratbike guys like flat black and DON"T like 'fancy'