In theory, this should prevent users from creating forks because it will devalue their stake and it should save a lot of energy. Proof of Stake sounds like a good idea, but ironically, there is the “Nothing at Stake” problem.
What Is Altcoin?
Because mining Bitcoin is costly, it is not smart to waste your energy on a fork that won’t earn you any money, however with Proof of Stake, it is free to mine a fork.
An example of a nothing at stake attack is an attacker buying lots of “old stake” from users inexpensively inexpensive to users who no longer have stake in the currency. This can be made convenient by offering small payments to users for uploading their wallet.
Eventually after accumulating enough “old stake”, the user can begin creating blocks and destroying as many or more coin days than the network was at that time.
Altcoin Trading for Bitcoin
This block generation can be repeated until it catches up to and beats the current main-chain very cheaply. There are also “stake grinding” attacks which require a trivial amount of currency. In a stake  grinding attack, the attacker has a small amount of stake and goes through the history of the blockchain and finds places where their stake wins a block.
In order to consecutively win, they modify the next block header until some stake they own wins once again. This attack requires a bit of computation, but definately isn’t impractical. Because these attacks exists, including Peercoin  and Blackcoin  proof of stake cryptocurrencies have “master” public keys that control the blockchain.
This class of cryptocurrency is either insecure or centralized, however proof of stake based on a PoW currency is useful in some systems because gaining stake is costly, but it isn’t workable for bootstrapping distributed consensus.
It is an application layer protocol and tools can be built on it like websites can be built on HTTP. These rigs can run either Windows or Linux. If you are going to have 3 or less, Windows is ok. More than that you really want to think about using Linux. With Windows you have to set up an application that allows you to access the entire GUI desktop, and unless you pay for each copy of windows, it will update and reboot itself at inconvenient times.
It includes every single step you need to do in Linux to make it work. You can probably max out at about 5 mining rigs at the place you live. First year of mining pays for the rigs, second year is all profit. For more than that, you are going to want a dedicated space with more power and airflow for cooling.