All the versions of Free Rider 2 as far as I'm aware.  
This git contains the original 2008 build that's widespread, but also the swf files that used to be hosted on trackmills site.  
These updated versions contained new vehicles, slight tweaks in physics, and undo menu buttons).  
But these were never mirrored on the webz as when attempting to download them manually, it wouldn't work once you had the SWF.  
As the game checked the URL the game was running from and would "Return;" if something was sus.
  
So I've also used JPEXS Flash Decompiler to patch out the weburl DRM from the updated versions, so they're still playable in 2021.  

You could view them in this order:  
V1 - fr2-2008.swf  
  * Initial release  
V2 - freerider2-tracksize1.0.swf  
  * New menu buttons  
  * Slight physics change (I remember auto levels broke at this time)
  * Wheelchair added  
  * Skateboard added
  * Web URL DRM
V3 - play.swf / create.swf  
  * Scooter added  
  

SWF URLS:
http://trackmill.com/free-rider-2/game/gameloader.swf
http://trackmill.com/free-rider-2/freerider2vars.swf
http://trackmill.com/free-rider-2/game/create.swf
http://trackmill.com/free-rider-2/game/play.swf
http://trackmill.com/free-rider-2/frwithad.swf
http://trackmill.com/free-rider-2/freerider2-tracksize1.0.swf