| smm | WRAP SIMD Message Data |
| smmstore | SimpleMind Local Mind Map Data |
| smmstyle | SimpleMind Mind Map Style Data |
| smmx | SimpleMind Mind Map Data |
| smnt | SediMeter Network Definition Data |
| smo | SmartMorph Animation |
| smol | Spartan Molecule Data |
| smp | BrainVoyager QX Surface-based Statistical Data |
| smp | IMail Server Mail Message |
| smp | PhotoImpact Gallery |
| smp | Reason NN19 Sampler Instrument Patch |
| smp | SmartMusic Performance Data |
| smpak | SuperMemo UX Data |
| smpkg | SmartMusic Package File |
| smpo | SpeedView Meta Object |
| smpx | SmartMusic Accompaniment File |
| smr | Spike2 Time Views Data |
| smrx | Spike2 v7 Time Views Data |
| sms | My Phone Explorer SMS |
| sms | WRAP Salinity Message Data |
| smt | Apollo HiPer-SIx Database Memo |
| smv | Snes9x Captured Video |
| smx | SmartMusic XML Data |
| smx | STATISTICA Matrix File |
| smx | SysMetrix Skin |
| smxx | Autodesk Revit Exchange Data |
| smz | IBM SPSS Graphboard Template Chooser Shape |
| 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 |
