ristretto media is a collection of additional fonts to be used with SharedMedia / LibSharedMedia. This list is growing quickly (we have five fonts in the pack as I upload this, and sixty six more to follow up on, add to the pack, and release. This will happen in very fast succession as each of the font authors gets back to us).
rM is the result of a spirited debate on Alasin:Users (Mumble server, fun place to hang out, that stuff) last night. Essentially, it is a collection of painstakingly researched "truly free" fonts, in other words, free as in beer and thought. This makes it possible to use and re-use (feel free to tear the collection apart, use the font standalone in your own work, make a new collection with them, parts of them, anything goes) the fonts whichever way you like.
Copyright and Ownership?
None. The original font authors made those fonts available to anyone, for any use, anywhere. Note: while this is true for the five lines of the lua file and the fonts, the embedded libraries have their own Copyright and Ownership status. Refer to those for more information.
Yes. All fonts are obtained either from the author themselves or the author's authorized distribution. This means you won't get a font that has been "accidentally" placed into the public domain or one with the copyright notice missing.
Shameless pluggage: If you're looking for a guild, maybe even THE guild to await the Cataclysm, a small group of grown-ups where the tone is hearty but the bigots, drama queens, greedsacks, and braggarts aren't welcome, the join us on Nesingwary-US (Alliance). Alasin is all that, and more. Plus you get to tell me how much I suck