Trading is a lot better that mining. You just need patience and some reasearch and you can get yourself a mansion in a few years. Mining is too expensive for me and for a lot of people and I can only afford the electricity cost of using my computer.
In fact, mining is not a very expensive system, it is a bit costly to start with, but the system is able to take its own expense, in fact, you can use your video cards for other purposes, it's a totally personal situation. Electricity fee is not something to be paid for.