That's right, and you probably thought that Nintendo's upcoming 3DS was a cheap way to jump on the 3D bandwagon. An Indian provider is set to release a cell phone called View D sporting an glass-less 3D screen for a mear 69 euro's. I knew 3D cell phones were coming, but so affordable? It probably uses the same technique used in the 3DS by showing two different images wich will give a 3D effect within a certain viewing angle: http://www.techshout.com/mobile-phones/2010/26/3d-phone-dubbed-view-d-from-spice-mobile/

Seeing that it's a fairly simple and cheap technology, i think we will see a lot more devices sporting this kind of screen in the future(PSP2 even maybe?).

I'm placing my money on having to use anaglyph glasses for that price

Since when was it simple and cheap?

Parallax screen is a simple technology and small size arent expensive to produce.

If cell phones start using this technology it will really take the wind out of Nintendo's sail.

If it's that simple, I wonder why it took so long to see such technology out for consumers.

It doesn´t matter to me. All cellphones could have glass-less 3d, but none of them would have oot 3d (and future original zeld 3d), mario kart, or mario 3d platformer, pilotwings, pokemon, or maybe even smash bros 3d, etc on them. which could render them unappealing to me. (even nintendogs :p)

3D 21" monitor 3D vision.... 350 euros one year ago. There is no reason for 3D to be expensive, it's just cause it's not a widespread tech...

Autostereoscopic screens have required a lot of research. They have multiple problems like sweet spots, which don't make them great for consumers. Things are getting better, but for now it's only really practical for handheld devices like phones or the 3DS. 

The actual manufacturing of one of these screens is actually a relatively cheap. I wouldn't exactly call the method simple though. It sounds simple, but it's not when you get into the nitty gritty.

It took so long because support and demand wasnt there yet.