Yes, there is! During pre-sale you get 30% discount for an investment equal or greater than 50 ETH. 20% for an investment in the 1-50 ETH range. 15% discount for an investment below 1 ETH. During main sale, the percentage of discount offered will gradually decrease. 20% discount for an investment equal or greater than 50 ETH. 15% for an investment in the 1-50 ETH range. 10% for an investment below 1 ETH. Starting from the second week and onward, no discounts will be offered.