File extensions beginning with Symbols and Numbers

File Extension Description
$$$ OS/2 archive file (i.e. archives.$$$, keys.$$$)
$$$ Temporary file
$00 Pipe file
$DB Temporary file
$ED Editor temporary file
$O1 Pipe file
$VM Virtual manager temporary file
)2( LHA archiver temporary file
0 Compressed harddisk data
001, 002, ... Split parts of a single whole file
0B Printer font with lineDraw extended character set
1 Fax
1 Fax
1 Roff/nroff/troff/groff source for manual page
123 Spreadsheet
15U Printer font with PI font set
1ST Usually README.1ST text file
2GR 286 Grabber File
301 Fax
386 Windows virtual device driver
386 Intel 80386 processor driver
3DMF QuickDraw 3D Metafile
3DS 3D Studio Graphics format
3DT Database in which the meta-data of a 3D Topicscape is held
3FX Effect
3GP Mobile Phone Video
3GR 386 Grabber File
3T4 Binary file converter to ASCII
4C$ Datafile
4MD Musical file
4SW 4DOS Swap File
4TH FORTH source code file
555 16 bit per pixel image file format (5bit per component)
668 Music (the mixing is always at 12048 Hz)
669 Music (8 channels)
6CM Music (6 Channel Module)
75 75x75 dpi display font
7z 7-Zipped file
8 A86 assembler source code file
83p Executable program for TI-83 Plus Graphing Calculator
85 85x85 dpi display font
89p Executable program for TI-89/89 Titanium Graphing Calculator
8BF Adobe Photoshop compatibile filters/plugins
8CM Music (8 Channel Module)
8M Printer font with Math 8 extended character set
8U Printer font with Roman 8 extended character set
8xp Executable program for TI-83/84 Plus Graphing Calculator
91 91x91 dpi display font
96 96x96 dpi display font
@@1, @@2, etc. Hidownload temporary file
___ Adinf table
~$~ Temporary file
~H Cardfile heap
 !ut Unfinished µTorrent download