Further info, private vessel registrations in NSW Australia must end in 'N' (for New South Wales)
Leads to many creative names. some can't be repeated here.
There's a boat moored near mine with the name "In a Meeting" and rego no "INAMEETN". (I've also seen a boat named "MYARS", but it has off the shelf rego.)
Registration "number"can be all letters, or letters and numbers. You can apply for a custom registration instead of the auto allocated one, but you pay for it.