If you ever think about it, redstone seems useless and piles up in your chests. That's because you haven't made anything with it! This page is dedicated to redstone creations for people's useless redstone. Feel free to contribute any creations you've created!
Redstone display
There are many ways to show a very short video in Minecraft using a variety of pistons and colored wools. However, they are bulky, complex, and require a new base design for every new video. Luckily, along with the new Redstone lamps came a new method: LED displays. This article will explain the new concept and show you how to make one.
The idea is based on scoreboards found in school gyms and sports arenas. However, a scoreboard in Minecraft would be of almost no use in SMP and they are quite primitive. A little television screen would be more useful in SMP than a scoreboard. That's what this article will show you. To make this "Redstone display" you're going to want to use Creative mode, and a large space, about a 15x15x15 block cube. Just remember: the bottom 2 layers of the cube have to be underground for this to work!
Redstone False-3D Lighting Monitor
This is a conception based on several uses, this can be done in multiple ways but for this tutorial we're only going to give you one example of how to build and use this contraption. 
This is the False3D Monitor, if you place a second row of Sticky Pistons above the first row you can produce 2x2 pixels. To complete the look of the monitor, you need to place blocks in front of the sticky pistons to determine what color the pixels are, example: Wool. This happens because when the sticky piston pushes the "pixel block" and then the shading and the 3D cause the pixel to visible by the player(s). This can generally be used for any purpose regarding visuals, it can also be used for a mob trap if used properly.
Redstone programmable music
To make a programmable redstone music machine you need glass, redstone torches and repeaters, note blocks, pistons, and of course, redstone. Make a vertical square of a building material missing two alternate corners. Then set up pistons to a clock to make the square rotate through the blocks. Repeat the square for each different note. Set up a redstone torch followed by redstone then a redstone repeater inside the square so the redstone repeater outputs a current into a block then set up redstone on the other side of the block and then connect to a note block. Repeat for each note. Then replace some blocks with glass and turn on the clock that rotates the square. Notice that the notes play when a block crosses the redstone repeater but not when glass crosses it. The clock speed is the tempo and the glass and solid blocks are the notes. The note blocks can also be seen as the instruments. With this you can program a tune for your house or a server.
Farming
Why not make automatic farms, like chopping sugar cane on a clock? See Tutorials/Automatic Farming for more.
Aesthetic Redstoning
With leftover redstone, why not pretty things up a little bit? Putting the redstone underground can make it look great.
Annoyance Redstone
In order to make a noise machine, you can simply put a door under someone's house and attach it to a pulsar. Another type is to make a cobblestone generator and have a piston pushing it at a regular basis. Smoke generators also work well.
Fast spawner
This is a machine that relys on a clock to dispence items as fast as possible (Doesn't need alot, You can handle it) Video Tutorial link:www.youtube.com/watch?v=3pq_Iut5B6Y&list=PL99694B823899326D&index=8&feature=plpp_video (Just copy+paste it into the adress bar)