Irony.

I've just been to see Kick-Ass.  It's hilarious, feel free to go and see it.  During this film about an ineffectual superhero I came up with a new definition of irony:

• irony n. (pl. -ies) laughing at a film portrayal of a man who overestimates his own strength and is far punier than he imagines, then discovering that you can't unscrew the cap on your bottle of sparkling water.

I had to take it home after the film.  I still can't get the top off.  It's on my desk right now, taunting me; mocking me.  It's my new arch-enemy.

***************Update***************

Briony has just returned home and has opened the bottle for me.  It is no longer my arch-enemy; she is.