Three characters, .org, X-to-Y. D2N reads as data to network, donor to nonprofit, or diagnosis to next-step.
Donor to nonprofit is the transaction the entire charitable sector is built on, and the infrastructure serving it is a real industry: giving platforms, donor-advised funds, payment processors, and transparency initiatives. A name that states that relationship in three characters would be well placed for any of them, and the .org is exactly the right extension.
Data to network fits research and open data work, where the whole task is getting information out of silos and into shared infrastructure.
The X-to-Y form is what makes this readable rather than arbitrary. It hands the reader a relationship to complete instead of three letters to memorise, which is why names in this shape stick after a single exposure.
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