There are some confusions here, which it's worth sorting.

You do PAY or get PAID in BTC, but as has been said, you can purchase a contract to receive USD (This would be a call, currently. A BTCUSD call to be specific.)


So go buy a call at .5 BTC / USD.

Step 1: Send us 100 BTC
Step 2: Bid on a BTCUSD call at Strike of .5 in, say, 5 months. Price them at .001 BTC per, and bid on 100,000 of them.
Step 3: Wait for stupid longs to write these calls. They will have USD escrowed.
Step 4: Happily for you, bitcoin drops to $.50 per, or in BTCUSD terms, rises to 2 BTC-USD. Your calls are in the money.
Step 5: Buy 50,000 BTC for $25,000
Step 6: Trade your 50k BTC for $100,000 dollars.

You netted:
$100,000 US
-$25,000  costs to buy cheap BTC
-  $3,000 to buy calls
---------------------------
 $72,000


That is in no way stacked.

On the flip side, someone with the $100k got $3k in interest; I'm thinking options like this need to be offering roughly 15 to 18% returns for USD holders to pique interest, so I'd say that this would be roughly a 2 month timeframe at the suggested price. Of course, as you know, there are many, many variations on this.