The whole concept of drive letters is actually ridiculous and a flaw almost exclusive to Microsoft.
Really?
Operating systems that use drive letter assignment
* Digital Research CP/M, MP/M, Concurrent DOS, DOS Plus and DR-DOS
* 86-DOS
* IBM PC-DOS and Microsoft MS-DOS
* MSX-DOS
* Elektronika BK operating systems: ANDOS, CSI-DOS, MK-DOS
* PTS-DOS
* Atari TOS
* SpartaDOS X
* GEOS
* SymbOS
* OS/2 / eComStation
* Microsoft Windows
* Microsoft Xbox video game console operating system
* FreeDOS
* ReactOS
* Symbian OS
* DexOS
* Miraculix