I paid $30 for mine. I think they originally had a much higher price tag which would have been too much money. Now I am seeing them around for $15 on bargain websites which is a steal!!
The Fingerist is awesome provided you don’t pay too much for it or worry about looking like a dork! Essentially it holds your iPhone or iPod Touch and routes the audio to a 1/4 inch output or to a speaker. It also provides a neck and a strap to support your hands while you play the music app of your choice. And there are tons of cheap guitar apps out there. I use the WaveSynth general midi keyboard app. It is apparent from my cable management issues in live performance that we are not going for rockstar posturing so the keytar schtick doesn’t do me any harm. Highly recommended piece of gear and a wonderful conversation starter at gigs!