The HMS Astute...probably the most awesome submarine ever built? Seriously look it up, it shouldn't need refuelling for 25 years (and no that's not because it won't move for the next 24 years and 11 months), it's incredibly stealthy, it carries enough sigint equipment to listen to almost all of our mobile phone conversations and its got 39000 acoustic panels on its surface to hide from radar! Absolutely insane if you ask me. Of course, what really sets it apart for me is the fact that the crew hold theme nights once a week - and sunday roasts! It does admittedly cost nearly £1 billion, but someday when I make my money I'll buy one.