We've all been there, headphones on, getting into the groove, then you realise you've been singing out loud for ten minutes. Watch the footage below...
In all seriousness though, this happened to the chap in this video, which is now going viral. Point of note would be the George Osbourne lookalike in the foreground who barely looks like he can keep a straight face. As for the guys singing, well noone sings well with headphones on now do they...
Watch the man singing Rihanna on the tube below
As for the chap in the video, if reports are to be believed he is a singer called Infecta, who you can find here.