Caution: data were compiled by an empty burned out husk of an engineer. There may be typos and omissions.
Screw threads
Table of screw threads, sorted by diameter then pitch. Lists standard and nonstandard sizes, with their uses and historical/locational data.
Video resolutions and timings
Table of video/display/sensor resolutions, sorted by lines then columns. Also lists timings/modelines for the signals.
Serial ports information, baudrates
Serial ports description. Modem control lines, levels, buses. Serial communication speeds; UART, CAN, automotive...
could be handy for someone
LEDs - Light Emitting Diodes
Tables and lists of light emitting diodes data. Wavelengths and their uses, common color combinations, smart LEDs.
Tools: diameters of shanks, cutting/grinding wheels, circular saws
Tables and lists of dimensions of power tools small and large, from dremels to big angle grinders.
Common shank diameters, arbors hole diameters.
RJ45 and RJ11 pinouts
Pinouts for ethernet and phone jack connectors; network, phone, RS232/422/485, CAN, MIDI/DMX, 1-wire...
Stereoscopic 3D video
HDMI-oriented 3D video types, standards, formats