Does Minecraft ever go on sale?

I'm wondering if the game ever goes on sale or anything? $30 is a little out of my range, especially since I haven't been able to demo the game or really get a feel for it beyond playing it for about 30 minutes at a friends house. It seems like it's a lot of fun with a good community to boot. I have played games like Terraria which I also enjoyed but it seems like the 3d aspect to minecraft gives it so much more potential.