Looks like
Adobe AIR and
Microsoft Silverlight are getting competition:
Appcelerator Titanium has been released as public preview version. Basically it works similar like AIR: It's a native browser client running the web app. The difference to AIR: it's open source and your app can be distributed as single package, without the need of installing something like the AIR runtime before this. But I guess it will still need an installed flash player if you plan to include an .swf file in that package, unfortunately (unconfirmed yet), otherwise Titanium would be the perfect tool for distributing flash games as standalone versions on end user PCs, IMO.
Why do you need anything for standalone versions of flash games? Can you not just let people download the .swf?
Is Titanium something specifically for flash?