btct offers 84d (i.e. 12w) options.
However I've made some calculations, and locking 2.3 BTC for a 0.2 premium equals to a weekly gain of 0.01666667, which I think will be lower than the dividend that AM will pay during this period (assuming 0.0290 weekly dividends, that would be 0.01957273 adjusted to what I could buy now with 2.3 BTC), so I could as well buy some AM-PT shares with those coins and have a higher return.
Would you accept either:
• 84d, 2.3 strike, 0.28 premium
• 56d, 2.3 strike, 0.16 premium
?
If you think the share price won't fall in the following 12 weeks, you can make the same amount of money right now, instead of over a period of 12 weeks, by offering 12-week put options with a strike price of the current ASICMINER price and a premium of expected_average_dividend*12.
So if you think 0.04 BTC/week is a high average dividend (I think it is), then you should be willing to sell 12-week put options for 0.48 BTC per contract with a strike price of 4.24 (current ASICMINER-PT highest bid).
If you do this you could buy 1 extra ASICMINER share, and increase your profit further, if the share price doesn't go down.
So in essence you'd be getting an instant, locked-in profit in exchange for a lack of profit in case the share price increases.