Big boss just released a mobile substrate extension that allows you to display any app on a TV screen. It works great so far, however it is a work in progress.
From Big Boss:
Support for the springboard is currently disabled and there is no landscape mode. They also said certain Open GL apps like Google Earth might not work. I've been playing Silent Hill all night, because it is displayed in portrait mode.
The hack has a great little app to toggle on and off the apps you want displayed. Check it out under the big boss source. I have only had one problem with it when safari stopped displaying. A simple restart fixed that.
From Big Boss:
Features
TVOut capability can be set on a per-application basis.
A background image can be displayed by placing a JPEG file at the following location:
/var/mobile/Library/TVOut/wallpaper.jpg
Known issues
Support for displaying SpringBoard and the statusbar via TV-out is currently disabled.
Certain OpenGL-based applications (such as Google Earth) do not display properly.
OpenGL-based applications do not work when a background image is set
Applications that already support TV-out (iPod, YouTube) also have issues with background images; they also fail to play video if the application itself (and not just the video window) is set to use the TV display.
Todo
Fix known issues.
Add support for landscape mode.
Add per-application settings.
Support for the springboard is currently disabled and there is no landscape mode. They also said certain Open GL apps like Google Earth might not work. I've been playing Silent Hill all night, because it is displayed in portrait mode.
The hack has a great little app to toggle on and off the apps you want displayed. Check it out under the big boss source. I have only had one problem with it when safari stopped displaying. A simple restart fixed that.