I would invest my bitcoins in an offline or real world kind of business. The only problem is that bitcoin is still not well known and that when investing it in the real world no one will accept it.
Bitcoin investment is becoming popular nowadays so it's good if you will include bitcoin as your offline business. How? By just storing it your cold storage and just wait for years to come. Be busy on other things while waiting for bitcoins price to increase and by that way you will be having good decent profit in the end.