Minecraft is really an incredible game, the sense of freedom you achieve just from loading the game and being spawned in the hugely immense world. You decide where you live from the off; near the beach, above the sea, under the sea, under the ground, in a cave, in a treehouse or even in a wooden lodge; handbuilt, of course.
It's for those reasons that I truly love this game. I love most games with a sense of freedom like this.
I'm sure you can find a mirror to the 'free' version somewhere on the interwebs ;) and I'd recommend trying it out, if you like it; spend some money and support Notch, he is an awesome guy.