Using the EBow or Ebow Plus for guitar:

Invented by Greg Heet in 1969, the "electronic bow" or E-bow is a small battery operated device used to create violin like effects on the electric guitar. It creates infinite sustain using an electromagnetic field to resonate the string it is placed over, which is then sent to the amp like a normal guitar strum through the pickups.

For guitarists constantly in search of new sounds and effects to stand out from the crowd, the Ebow, and PlusEbow offer a distinct and variable alternative to traditional strumming. By utilizing the infinite sustain, guitars can create sweeping solos that are similar to the sound of a synthesizer pad or organ without changing instruments. Additionally with the addition of the harmonic mode of the 4th Generation E-Bow, PlusEBow, it is possible to reverse the phase of resonance of the string to cancel out the fundamental frequency allowing for the harmonic to shine through. The result is an infinite amount of "feedback" from the amp that are popular in rock and roll songs at the beginning and end of songs and guitar solos.
Ebow Plus
If you are interested in purchasing an EBow or PlusEbow here are a few alternative uses that you may find interesting:

Fade In/Fade Out - With practice, it is possible to control the EBow so well that you can fade the volume of the strings sound by moving the EBow closer or further away from the guitar. Expert EBow users can create sounds similar to a violinist using more or less pressure on the string with their bow.

Snare Drum - Gino Robair was the first believed to use the EBow in an entirely different form combining two of them to resonate the metal snares on the bottom of a snare drum to create theromine like sounds.

Sweeping Pad Effect - When layered with loads of reverb and delay, the EBow can take the electric guitar to whole new level. Adding a wah pedal to the mix allows for even more control of the tone and harmonics. Harmonize with a traditional keyboard to create echoing spacey sounds that will put audiences in a trance.

The beauty of the EBow and EBow Plus is that there is no wrong way to use it. Any new and original sounds it is capable of producing can only be used for your benefit. If you are unsure whether it will find a home in you guitar effect arsenal, rest assured it will at the very least open your mind to the potential sounds an electric guitar can make.