It must be able to generate with each start an unique config.
Has session storage or not
Has local storage or not
Has indexed DB
Has IE specific 'AddBehavior'
Has open DB
DoNotTrack or not
Full list of installed fonts (maintaining their order, which increases the entropy), implemented with Flash.
A list of installed fonts, detected with JS/CSS (side-channel technique) - can detect up to 500 installed fonts without flash
Plugins (IE included)
Is AdBlock installed or not
Has the user tampered with its languages 1
Has the user tampered with its screen resolution 1
Has the user tampered with its OS 1
Has the user tampered with its browser 1
Touch screen detection and capabilities
System's total number of logical processors available to the user agent.
Internal HashTable implementation detection
List of supported gestures (for touch-enabled devices)
Video and audio codecs availability
Audio stack fingerprinting