Mining crypto-currency, does anyone do it, is it only done with an...

...automated program (it sounds really interesting)? Also sounds fun. Do folks actually make "real" money from it? I know crypto-currency can be traded on exchanges etc and you can also use it to pay for selected goods and services. I'm not just talking Bitcoin, also Litecoin, Quarkcoin, Peercoin, Primecoin etc. Btw, do you have to keep your pc running 24/7? What if it crashes?

To an absolute beginner like me Quarkcoin sounds interesting, maybe it's just that it seems the easiest to understand from a 5 minute glance. I'm sure they are all interesting and fun and hey, if you can make money from it, all the better! Thanks.
I had never heard of Quarkcoin http://www.qrk.cc and http://www.quarkcoins.com