My favorite was the Channel Islands GLX150.
I was gonna say you totally forgot about the uber square, actually a collab! But I see Will promptly pointed that out.
Have to say even though I don't have the prestige of owning one of the majestic gw-t5030s, I'd say it would have to rank as the my favourite and indeed one of most special collabs of all time.
Anyway... since I can't cough up a pic of the uber square, here's my second favourite collab of 2013:
And if we can count casio's 30th anniversary year (which is longer than a normal year!) this one also falls under the category:
The 'Edison'
released around the rising reds...
Sent from the 'droid.