| smpo | SpeedView Meta Object |
| smpx | SmartMusic Accompaniment File |
| sms | My Phone Explorer SMS |
| sms | WRAP Salinity Message Data |
| smt | Apollo HiPer-SIx Database Memo |
| smx | SysMetrix Skin |
| smx | STATISTICA Matrix File |
| sn | Elnec Programmer Serialization File |
| sn1 | Drive Snapshot Backup Data |
| sn2 | Drive Snapshot Backup Data |
| sn3 | ChessDB Name Data |
| sn3 | Drive Snapshot Backup Data |
| sn4 | Drive Snapshot Backup Data |
| sn4 | Scid Name Data |
| sn5 | Drive Snapshot Backup Data |
| sn6 | Drive Snapshot Backup Data |
| sn7 | Drive Snapshot Backup Data |
| sn8 | Drive Snapshot Backup Data |
| sn9 | Drive Snapshot Backup Data |
| sna | Drive Snapshot Backup Data |
| sna | ZX Spectrum Emulator Snapshot |
| snag | SnagIt Capture File |
| snagitstamps | SnagIt Stamp Archive |
| snagstyles | SnagIt Style Archive |
| snapfireshow | Corel Snapfire Show Data |
| snapshot | VMware ThinApp Snapshot File |
| snb | S-Note Data |
| snbkp | S Memo Backup |
| sne | Spectronaut Experiments Data |
| snes | SNES ROM Image |
| snf | Starry Night Data |
| snip | Microsoft Windows Snipping Tool Snip Data |
| snl | EGrid32 Form Snippet |
| snm | Netscape Mail Index |
| snn | STATISTICA v7 Neural Networks File |