Wikipedia
Variax
Variax is the name of a line of guitars developed and marketed by Line 6. They differ from typical electric and acoustic guitars in that internal electronics process the sound from individual strings to model (replicate) the sound of specific guitars and other instruments. The maker claims it is the first guitar family that can emulate the tones of other notable electric and acoustic guitars. It also provides a banjo and a sitar tone. The Variax is currently available as an electric guitar, but modeling acoustic guitars and modeling electric bass guitars have been available in the past.