KOI8
From Just Solve the File Format Problem
KOI8 is a family of 8-bit character encodings primarily for Cyrillic alphabets. Character codes 32-126 are identical with the corresponding ASCII characters. Cyrillic characters are ordered in phonetic correspondence to ASCII characters in the bottom half of the code table, not in native alphabetical order. The most widely used of these encodings is the Russian KOI8-R.