The abbreviation stands for RSX:
- Rhein-Sieg- Express, a regional express train line in North Rhine -Westphalia and Rhineland -Palatinate
- Only Real-Time System Executive, then Resource Sharing Executive for RSX -11
- The graphics processor of the game console PlayStation 3, see RSX ' Reality Synthesizer '
- Agfachrome RSX, a professional slide film from Agfa
- The former entry-level road bike from Shimano
- Resident system extension, see Locomotive BASIC and CP / M
- RS: X, an Olympic discipline in windsurfing