The codenames for every major Debian release are named after characters from Pixar’s Toy Story franchise. Debian’s unstable release is fittingly named after Sid, an unstable character from the Toy Story movies.
I actually like Mint’s naming scheme, of alphabetical women’s names that end in an a sound. Only one problem: They decided to go with the minor upgrade cycle during Mint 17. The 17th letter is Q. I’m frankly surprised they were even able to think of “Quiana.” That’s why the rest of the 17s were R names, Rafaela, Rebecca etc. so now they’re off by one.