- This simulation from PhET shows two-gas diffusion with adjustable parameters.
Andrew Duffy of BU also has two simulations on this topic
- Brownian Motion, with variable temperature
- One or two-gas diffusion, also with variable temperature
- This simulation by B. Surendranath traces the motion of a massive dust particle undergoing Broanian motion; the number and mass of the air molecules and their temperature can be adjusted.
- On a related topic, this additional app by Andrew Duffy simulates diffusion-limited aggregation with variable attraction.