Collection of all pass-through files?

[alaskamapscience]

Is there a way to generate a collection that contains all the files that are passthrough-copied to the output? I've tried adding tags to the data.json file for the directory, but can't figure out how to get the individual files to be processed into a collection if they don't have a filename extension that matches one of the template engines. In particular, I have a directory of binary files that I want to make be individually downloadable.

[edthedev]

In general, a much simpler pass through option would be welcome.

Even just an option to add one line per file to .eleventy.js would be welcome.

[deathau]

This one is old... But does anyone have any solutions or workarounds? I find myself wanting to build a list of pass through files, but can't figure out a way to do it automatically.