In Reichenbach fall: John tells Sherlock that everyone gets a tabloid nickname. Then he says "Subo (or Soobo), nasty nick". I assume he's referring to some other tabloid frequenter.
Who is Subo?
SuBo is Susan Boyle:
a Scottish singer who came to international public attention when she appeared as a contestant on the TV programme Britain's Got Talent on 11 April 2009, singing "I Dreamed a Dream" from Les Misérables.