Three characters on the .org, in the letter-digit-letter shape that reads cleanly and types fast.
T3I has no entrenched meaning, which leaves it open for an organisation to define. Technology, transformation, or training on the T; innovation, institute, or intelligence on the I. Institutes and initiatives in particular tend toward this kind of compact naming once their full name gets unwieldy, and most of them find the good short addresses are long gone.
The .org is doing specific work. On a commercial extension a three-character string reads as a startup; here it reads as a body with a formal name that people have shortened. That’s a useful impression for a research centre, a standards group, or a foundation.
Three characters fits everywhere an organisation’s name has to go: reports, badges, footers, partner slides, and email addresses that people get right first time.
The name is listed. Enquiries welcome.