Haha this was the work of
midnightmagic who intentionally was trying to omit 1 satoshi from the blockchain forever in honor of satoshi and the fact that satoshi is missing. Then he messed up and lost the fees too.
In block 124724, I deliberately and specifically underpaid myself by 0.00000001 ฿, which is colloquially known as "1 Satoshi" after ฿'s creator and due to a lack of a good name for that amount of ฿ money.
To make absolutely sure that I was doing it on purpose, I set the reward value to 49.99999999, which meant that I inadvertently threw away the transaction fees which I could have allocated to myself.
I did it as a tribute to our missing Satoshi: we are missing Satoshi, and now the blockchain is missing 1 Satoshi too, for all time.
♯♯snipped♯♯
So, this is a provably missing amount of the fees+1 Satoshi from the blockchain, from block 124724, which appears to be 0.01 + 0.00000001 ฿.
I did this by creating an option in my heavily customized client (derived from the git fork of bitcoind) which allows me to arbitrarily suspend the normal block reward calculation and underpay myself. The code itself only checks to ensure that I haven't *overpaid* myself. It doesn't at all care that I've *underpaid* myself.
I view this as a freedom in the protocol, and not a drawback.
blockexplorer.com has a display bug for that block which has not been corrected yet.