@anon92205803 – This is quite the entertaining subject to luxuriate in, isn’t it? 
@anonspaz – Your exhibition of ultra rare cards is exquisite! I am extremely impressed by your Articuno. I never realized this particular card existed – very, very cool
The rarest card in my possession based purely on restricted distributon numbers would be the Wonder Platinum (033/DPt-P). This particular card was awarded to the top three finalists in each age division at the 2009 Japan National Championship Representative Tournament. In total, it is speculated that only nine cards exist due to the distribution method (i.e. three (3) cards x three (3) age divisions). I obtained this card from a very good friend of mine 
I wish to expand on the concept of rarity by addressing “unique” cards. I do own three cards which are unequivocally unique and literally “one-of-a-kind”. I posted hyperlinks to my photographs due to potential size constraints of my single post:
• 2002 Battle Road No. 1 Trainer
• 2002 Battle Road No. 2 Trainer
• 2002 Battle Road No. 3 Trainer
The 2002 Battle Road Tournament Prize Cards have either a male or female illustration drawn on the card, depending on the gender of the winning competitor. In addition, every card is personalized with the name and regional conference of the winner. Ergo, every 2000 - 2002 Battle Road Prize Card is unique and incapable of duplication.
I wish I had a female version 
In regards to my detailed record of acquisition for the No. 1, please visit this thread for further explanation. The chronicle is curtailed, yet it feels odd to reiterate it again in a newer thread conversation. I purchased my 2002 Battle Road No. 2 and No. 3 from an eBay seller. The rest is history