General:
* Dash
* Hurry
* Scramble
* Rush
* Scamper
* Flit
* Hustle
* Scoot
More specific:
* Scuttle (for small animals)
* Scurry (for small animals)
* Bolt (for sudden, fast movement)
* Dart (for swift, quick movement)
* Streak (for fast and continuous movement)
The best synonym will depend on the specific situation you're describing. For example, if you're talking about a mouse running quickly, "scuttle" might be the best choice. But if you're talking about people rushing to get to work, "hustle" might be more appropriate.