Happiness is a bugger to write about, it really is. So, I'm not going to. In a startling break from established form, this is going to be a no-waffle post. Honest, it is.
There's so much music that I listen to when I'm happy that selecting a single song was stumping me. So, as I usually do in moments of indecision, I asked my wife what to do. She said "do a song that makes you strut, you're always happy when you strut". And she's right, I am - it's laughably-easy to spot when something suitably-rhythmic comes up on my iPod, because my entire gait unconsciously changes - my stride lengthens, my posture loosens, and a slight swing works its way into my shoulders. I probably look absurd, but I don't care. Because I'm happy.
And when it comes to songs to which I can really get my strut on, there's one example which stands out head and gently-swinging shoulders above the rest.
If that rhythm doesn't get you moving at least a little bit, there's every possibility that you are actually dead. Seriously, you should probably get that checked out.