We sill start off by walking though the different parts of a GIF file. A GIF file is made up of a bunch of different "blocks" of data. The diagram shows all of the different types of blocks and where they belong in the file. At each branch you may go one way or the other. The large "middle" section can be repeated as many times as needed.
post 
The explanation goes on for three detailed posts describing the many features that have found their way into this highly evolved file format.
**Application Extension Block** link
Example (Not in Sample File): `21 FF 0B 4E 45 54 53 43 41 50 45 32 2E 30 03 01 05 00 00`
The spec allows for application specific information to be embedded in the GIF file itself. The only reference to could find to application extensions was the NETSCAPE2.0 extension which is used to loop an animated GIF file.
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I spent most of my time at ETHDenver Hackathon tagging along with Duke Crawford, a regular at the weekly wiki hangouts, and a fan of Named Data Networking.
Duke has a vision and work in progress for increasing the density of sensory integration around words and ideas to make communication more efficient. See th.ai
Central to the work are animated gifs which capture soundbites from videos with animated transcription of the idea captured.
I daydream about embedding a `Dockerfile` to capture a small, drag-and-droppable picture which could be re-hydrated into an application. Important also would be metadata with cryptographic signatures or similar to protect against tampering with the encapsulated code.