There is a cheap ($149) and generic mini-USB micro projector now listed on Amazon. While not very spectacular in any regards, it has taken the pole position of cheap. It has no features and must be coupled with either a desktop or a laptop. It is USB powere.
Even in price, is isn’t anything spectacular. The Sanwa USB projector is similar in specifications and at $179, it only costs $30 more than the generic USB pocket projector.
More surprising is that Aaxa seems to be blowing out the Aaxa P1 Pocket projectors (refurbished) at $179 as well.