Effective immediately, hoppers are uncraftable. This is an issue that we have been putting off for a while now, but it's come to the point that the massive amount of hoppers (which used to be cheap and easy to craft) are causing lag on the server due to how they are used in massive farms. This change brings a price increase in hoppers, as well. You can now, however, sell your hoppers back to the server. You will get $2500 for each hopper you sell. Go to the redstone shop at the mall (Roger) to sell hoppers.