I have a few bitmain coupons for sale:
AntMiner C1 Coupon 50 USD
AntMiner S3+ Coupon 50 USD
AntMiner S4 Coupon 400 USD
Validity Time
2014-11-30 11:10:00
I'm asking 0.01btc each. These can be safely traded using the donate option on the bitmain site.