Three characters on the .org in the letter-digit-letter shape. Clean to type, clean to read, and it holds its form at any display size.
The S3 opening carries an association with object storage for anyone in cloud engineering, which gives it an immediate technical home. On the .org, that suits an open-source project, a standards effort, or a technical foundation rather than a commercial product, which is a genuinely useful distinction in infrastructure software where the open and commercial layers are usually separate organisations.
Outside that reading it’s simply three characters with no baggage, available to any organisation whose initials fit or who wants a compact mark.
The supply case hasn’t changed and can’t. Three-character domains across every major extension were fully claimed decades ago, and what circulates now is only what existing holders release.
The name is listed for sale. Enquiries welcome.