http://www.scribd.com/doc/209050732/MtGox-Situation-Crisis-Strategy-DraftThe $20M is on the Crisis Strategy Doc (actually its $22.4M USD - but with other assets it makes a total of around $33M)
Total liabilities $55M + (744K BTC * current price on stamp) = $501M
At current Bitcoin prices looks like they will be paying out liabilities at 15 cents on 1 Dollar (15%) ($500M/$33M)
Which means Bitcoinbuilder should be trading at 0.066 for break even (Though I wouldn't touch it anymore, even at .01)