Beyond engineering, the phrase appears in a few distinct (and likely unrelated) niches:
"bb@toot.works" is a Mastodon handle for a professional file editor named Bryan Brattlof .
In academic texts discussing internal combustion cycles (like the Otto or Diesel cycles), similar strings of characters often appear in OCR (Optical Character Recognition) scans of formulas. For example, in documents like Thermal Engineering by Mahesh Rathore , "Bb Toot" sometimes surfaces in fragments related to:
There is a reference to a TOOT Engineering T47 Titanium bottom bracket (often abbreviated as BB ) for high-end bicycles.