Minecraft Unbelievable Shaders Mod
I put this video together in 720p showing a mod called Unbelievable Shaders. Watch the video for the goods as it is pretty amazing I think..
EDIT: 1/24. For much better performance results with this mod, use the MT (multi-threaded) version of Optifine instead of standard. To do this without visual artifacts, get the Java 7 JRE @ http://www.oracle.com/technetwork/java/javase/downloads/jre-7u2-download-1377135.html
This video shows Optifine MT and Java 7 in action for better performance.