It turns out that rather than being rare collector's items, the 10, BTC exchanged for two pizzas have spread out to over a million different Bitcoin addresses since buying the is it possible to track a bitcoin transfer, not counting the dilute fragments that ended up in transaction fees.
As of blockon Feb 10th1, addresses have held the pizza coins since they were spent.
Bitcoin Transactions - from \
In other words it's possible to have "pizza coins" and "non pizza coins" in the same address and still be able to tell which are which. The shortest chain of transactions from the pizza purchase to currently held pizza coins has length 9, and the longest has length 6, All the pizza coins have been diluted somewhat with other coins.
The purest remaining are these BTC which are The most recent 9 transactions each only have 1 input, so it's easy to follow it back that far. In the next transaction back the pizza coins came from both the last but one input, worth BTC, and 5th from last input, worth The other inputs in this big transaction, worth BTC in total are the only non pizza coins introduced.
I also checked my wallet to see if I was holding any pizza coins. My 'strongest' has a purity of 1.
Finally, here's some data showing the month-by-month spread of the pizza coins: pizza payment of Edit 2: I don't mean to imply that the allinvain coins haven't been thoroughly looted. They have toucheddifferent addresses since being stolen and are currently sitting indifferent addresses, including 8 from my own personal wallet.
The exact same 8 as have pizza coins in them, it turns out.