s3h.org
In infrastructure software the open and commercial layers are usually separate organisations, and the open one uses .org. That distinction is genuinely useful and this name sits on the right side of it.
S3H is three characters in the letter-digit-letter shape, clean to type, clean to read, holding its form at any display size. The S3 opening carries an object storage association for anyone in cloud engineering, which on this extension suits an open-source project, a standards effort, or a technical foundation rather than a commercial product.
Outside that reading it’s simply three characters with no baggage, available to any organisation whose initials fit.
The supply case hasn’t changed and can’t. What circulates now is only what existing holders release.
The name is listed for sale. Enquiries welcome.