My red Felt F75 is:

'The Big Red Beast' (because it gets me into the right mindset for my training/racing when I get on a bike called 'the beast'.

'The Beast' (because same as above but sometimes I'm in a hurry)

'The BRB' (because...Big Red Beast/Big Red Bike, and later added the "Be Right Back' because I have a habit of saying 'Be right back' before a planned short ride and then coming back hours later because I was having too much fun.