.??_  Files ending in "_" are often compressed install files of the same
          name (e.g., .EX_ expands to .EXE, .DL_ expands to .DLL, etc.)
  .Y    Amiga Yabba Compressed Archive File
        Yaac Grammar File
        Desktop Color Separation Specification Yellow Layer (usually an EPS file)
  .Y01  Paradox Secondary Index (can be 01 to 09)
  .Y64  Commandos 2 Game Mission
  .YAB  YaBasic Source
  .YAL  Arts & Letters Clipart
  .YBK  Encarta Yearbook
  .YDK  Yusuf Data Recovery (unverified)
  .YENC  yEnc Encoded File (usually on usenet)
  .YLT  TheWord & Bible Companion Young's Literal Translation Bible
  .YMAP  Ygnius Computer Aided Thinking File
  .YMG  Yahoo! Messenger File
  .YNC  yEnc Encoded File (usually on usenet)
  .YPS  Yahoo! Messenger File
  .YSP  Bitmap Graphic (unconfirmed)
  .YUV  Color Space Pixel Format
  .YZ   Yac Compressed Archive File