After having played around a lot with Bitcoin, Litecoin (and all those other coin-thingies), a colleague of mine told me of an alternative: CoinGeneration!
You download their client “ThreadManager“, which allows you to run 1 thread for free (takes about 10 % CPU power for me). This generates about $1 per day.
Now you have the option to buy additional threads for $50 each, so each thread would generate about $30 per month. That means if you buy 1 thread, you have 2 threads in total which generate you $60 per month.
So you have your money back and even made additional $10 in the first month,
while every additional month makes you $60 / month respectively $720 / year!
Calculate it: For each $50 you spent, you get $360 per year. (imagine: spend $500 and get $3600 per year for doing nothing!)
It also offers an affiliate system so your referrals (and sub-referrals) generate cash for you.
Try it now: CoinGeneration