Example of my server logo:
Create cool looking firework patterns with wool blocks! By placing down wool blocks in a specific pattern, you can convert them into firework displays. It provides a neat effect and can spice up how your server looks in places such as lobbies.
Video explanation below text explanation.
To use this, place down wool blocks (the color being what you want your fireworks to be) in the shape of whatever you'd like (try to keep it less than 40 blocks or it may not show up). Select all the wool blocks with worldedit. Stand at a location where the +X and +Z axis has nothing remotely in the way. Type /shapedfirework, and command blocks will appear (and will destroy anything in their path). The wool blocks will also be replaced with more barriers (that won't break anything). Activate the command blocks to get a neat effect!
How to use/video explanation:
An example using my server logo: http://i.imgur.com/5NSF5SL.gifv
Based off of the MCEdit filter: https://www.youtube.com/watch?v=AJYPQof3yV
Source Code: https://github.com/ShinyDialga/ShapedFireworks