Start mining some coins right now. First you need to sign up to some mining pools.
I use for Litecoins http://pool-x.eu and for Feathercoin https://ftc.d2.cc.
You can have differnt mining task running on you GPU ore on you CPU.
I at the moment only using my CPU but it i get the GPU runing as well i will update the blog.
This is and great blog on how to get started with minerd
On Ubuntu install some programs
sudo apt-get install build-essential libcurl4-openssl-dev screen
Download program
wget http://sourceforge.net/projects/cpuminer/files/pooler-cpuminer-2.3.2-linux-x86_64.tar.gz
Unpack program
tar zxvf pooler-cpuminer-2.3.2-linux-x86_64.tar.gz
start a screen
screen
Setup an slave from one of the websites depending on what you want to mine
And the start the slave
./minerd -o stratum+tcp://pool.d2.cc:3333 -a scrypt -O username.2:pass
Se the output then
[2013-12-23 10:01:27] thread 0: 144612 hashes, 6.94 khash/s [2013-12-23 10:01:43] thread 0: 103416 hashes, 6.83 khash/s [2013-12-23 10:01:43] accepted: 1/1 (100.00%), 13.81 khash/s (yay!!!)
Press ctr+a and then d to exit the screen and now your server is mining for you.
The mining will spinn upp the cpu to 100% but i have not seen any big performance diffent on one of my webbserver will running apache and mining on the same host.
But would not start mining on prod server 🙂