Finally the 1.7 update came out for minecraft, and the most note able thing is: PISTONS! Mostly the sticky pistons (they touch a block and take it with) made from a piston and a slimeball (dropped by slimes which now have a use). Here's a video by :wtfminecraft from youtube showing the possibilities.

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You see the importance now? Thanks to wtfminecraft's tutorial I made a submerge able lava bridge.