Hamachi is a service used by individuals who are not in a reliable hosting environment and require assistance.
If someone wanted to host a game but either cannot be bothered to set up a proper environment with my router, firewall, or other variables that may be interfering, all he would need to do is simply load up Hamachi and join a Hamachi network. He would request that his contacts that would like to play with him do the same. Obviously this requires friends wanting to play with you to do, as since you are on a Hamachi network, anyone who is not on the network would not see your server if your server is not normally visible to the public.
