Yeah, I learnt (what? Firefox calls that a spelling error) to solve it last year. It became a major fad at my school - and several others, I've heard.
I solve the first two layers by intuition (without algorithms). Took me a few weeks/months of practice to master this bit. The third and last layer is solved with set sequences of rotations called 'algorithms' that I've memorised. These algorithms are designed to rotate or permute certain blocks without ruining the previously-solved other two layers.
My record is 20 seconds, but I average around 30 seconds. I also have a 4x4x4 Cube ('Revenge Cube') but it's nowhere near as fun as the classic. My friends owns and can solve a 5x5x5 as well but again it's not as fun as the 3x3x3 as they are mainly just memorising and applying algorithms rather than intuition.
Now, the Rubiks's Cube is fantastic stress relief or when I have itchy fingers. Or am generally bored. Fun fun fun!