In addition, our culture has slowly eroded the usefulness of printing parts. Parts are great if you fix things, but consumers don't fix things. They break them and buy a new one!
IMO 3D printing will provide a huge boon to 1-2 person commando hardware startups more than consumers, in the same way that access to free development tools and cloud services have been a huge boon to 1-2 person commando software startups. In that way, consumers lives will certainly be changed by 3D printing because of being provided more products, but not necessarily by actually owning them and printing things with the printers.
To me, the key is going to be the cost of the feed stock. Get it low enough and people will 3D print everything.
A side note, this weekend my 74 year old stepdad was asking me about the state of 3D printing. He has a mechanical engineering degree, so a bit atypical of his age group I guess, but he was really excited about the possibilities.
I also told him about HN so he's probably reading this now. Hi!
 Though probably much less environmentally sound!
Don't count on it. Paper isn't an environmental liability - all paper you can buy in the US and Europe is from sustainably farmed wood and recycling. As long and the resulting books are recycled, not inefficiently burned, it's fine.
Also, remember, the cost to maintain libraries isn't just financial, it's environmental as well.
Though forests used to be cut down for paper. That's no longer the case because it's not profitable anymore. Because of lack of demand.
But while the parent poster is right that virtually all paper today comes from sustainably farmed wood. That's still an ecological problem. Because sustainably farmed wood is not native to our eco system. Brazilian flora might take centuries to grow, so farmers would chop down local trees to plant European pine trees instead. Their propaganda, which the parent poster bought into, is that if you chop a tree to plant another, then no harm is done. But that's not how eco systems work. Local fauna cannot live in foreign pine trees, just as they wouldn't live in a concrete city. So many local species are now endangered or extinct because of paper farms.
I live on an area where a lot of paper farming used to happen. I had an American friend come here once. He told me the forest around the highway we were on surprised him. Because it looked nothing like the movies he seen, instead it looked just like Europe, with regularly spaced tall pine trees. He asked "is this where the monkeys are?", looking closely to the pines hoping to see one. Unfortunately, I told him, during my whole life here I have never seen a monkey in the wild. Even though this same place used to be the home of some really interesting species, like the golden lion monkey. But we could go to the zoo to see one if he wanted to.
Source of this is my experience as a local who used to be an active Greenpeace volunteer, back in the day.
For the record, I didn't suggest that replacing old growth forest with fast-growing trees foreign to the ecosystems is neutral or sustainable.
Most paper you can get is made from tree that are grown specifically to be made into paper (http://en.wikipedia.org/wiki/Tree_farm) - those are managed and replanted just like any other kind of farm. They are also brilliant CO2 sinks (as long as the paper isn't burned). Look for any of the organisations mentioned in the WP article -- ATFS, FSC or SFI -- next time you're in an office supply store in the US, similar schemes for other parts of the world. You'll be hard pressed to find paper that isn't certified as being sustainably farmed under one of these schemes.
I can't speak for Russia, but the disappearing old growth rain forests in among others Brazil isn't for paper production, it's getting cleared for farming or harvested for the exoticness of the wood (for furniture etc) - not for paper production.
To be fair, I was only considering the fiber-end of the equation. Processing fiber (from wood or recycled paper) is energy, and (in particular) water intensive.
I could say the same about a number of books I have bought at bookstores over the years. I mean, ask a librarian how well books hold up over time, and how often they need to be repaired simply from normal usage. And then when the paper itself begins to go south... (Admittedly, that was more of a problem before acid-free paper caught on.)
The universal response: "Fuck you I would if I could."
When the court system decides that Samsung can't make a phone that looks sort of like an iPhone, it's a good bet that courts will find that it's illegal to print, or assist printing of, a replica of some $megacorp object or part.
You know the part and can replicate its look... why not?
You wouldn't steal a cake, so why would you bake it?
Maybe I lack imagination, but I cannot imagine a plastic piece of junk that need to be tailor-made poorly.
When the cost of a PC went from $30k to $2k, most people couldn't see the revolution happening. Maybe I am the same fool.
I know a bunch of people printing off models of their characters from the game 'City of Heroes' (incidentally if you ever want to see how not to close a service, check out NC Soft's behaviour over the last couple of weeks) before the doors shut and a lot of them would probably pay a substantial amount for a slightly better quality painted one.
There's a huge difference between me building something for my own personal use, as opposed to building a product and trying to sell it.
As the quality of 3D printing improves I can see lots of companies doing this, especially for legacy parts.
I wish I could agree with your conclusion, but I have had a lot of trouble looking for "out of print" arcade game roms . I want build and use an arcade machine for my house (legally). However, it's amazing how protective old companies seem to be of people playing their games which they no longer distribute.
I get the feeling it will probably turn out the same with 3D printing out of production components.
 (for example) http://mamedev.org/devwiki/index.php/FAQ:ROMs#How_do_I_legal...
* One manufacturer and one manufacturer only of the parts for my particular wheelchair (A Quickie GTX by Sunrise Medical)
* High prices as customers often don't have any other options
* Occasionally the company won't deal with me as I'm only ordering 1 or 2 parts at a time, not hundreds
* Proprietary parts requiring complicated installation - unfortunately I can't direct link but have a look at any of the front brace/fork assemblies on http://www.sunparts.us/
* Slow shipping times from the US to Australia, requiring me to plan ahead for any future damage/repairs!
Anyways, I think this is a great development. If TE wasn't making much money on spare parts, might as well not sell them, and with companies like Shapeways around, it doesn't force every consumer to have a 3D printer, either.