Instant Apps - Fast, semi booting for Ubuntu with added security

I propose a way to boot ubuntu very quickly, with the purpose of using only a few apps.

User presses the power button of their computer, they then immediately hold down a key on their keyboard. E.g. the U key.

Computer starts booting. One of the first checks that it does is to see if the special key is being held down.

If it is the boot process loads a very, very streamlined system with a GUI and Internet access. Personally I think this should look like a ubuntuised, OSX Boot camp.

This half booted system would exist in ram and be separated from the main OS. Therefore making it very safe for Internet use.

The User can then select on this menu to run their browser, email client, IM program, Skype, to continue a full boot of the system or to shut down the system.

If the user needs to access a file on the hard drive, to add an attachment to an email or send a file over IM they should be prompted to boot the full OS. This should be able to be done without the user losing the current state of their open programs. Possibly this would also need to happen if the user tried to print in this mode.

The aim would be to reduce the time needed to get from a powered off computer to a quick google search or email check by 50%

This could possibly be done with a modded version of blackbox or fluxbox.