Minimum purchase amount of $25 give how many coins?

Can i pay with btc?

what is the pre-sale time?  and where to buy ?

Well, attracting buyers is only after fairness and security, and I think POS misses on those aspects.
Note however, that the mentioned POW was with respect to timestamping over tauchain -- and this can never be POS, because there are no stakes. Tau-chain begins with nothing, far to mention a coin, and the users set the rules=programs=p2p networks. Of course, when tau is on air yet empty, all participants including devs are totally equal.

I just came back from a meeting with Ohad (we happened to live an hour apart and met on Mastercoin hakaton) and got his permission to use this thread freely to demonstrate right on it my take on Tau-chain which will make it easier to understand some of the Tau-chain future use. it will take a bit of time and may be a bit annoying, and may not be all that great, but I think that it will help, so I apologies  ahead of time.  

I'm not a programmer so I don't really understand a lot of the whitepaper and I'm not sure whether I've got a right understanding from what I read or not, but  $1500 is a good excuse to try and work out wtf you are doing with this thing so here is my attempt:

Tau Chain creates a network of computers which work together as a kind of distributed truth engine.  Any computer within this network can submit a solution to a task which somebody wants completed, whether it is storing files, performing a calculation, or writing a piece of code to perform a specific function. The Tau Chain provides a flexible set of tools for the network to tell whether that computer is telling the truth about performing the task or solving the problem.

Through the inclusion of data about the meaning of words, and their relationships to each other - which has already been highly developed in a machine accessible way by search engine engineers trying to help computers to respond naturally to questions people type into places like Google, the Tau Chain would be able to apply the same logic to verify whether human statements are true or false, and to give people answers to logical questions.

This allows the Tau Chain network to perform a wide range of useful functions in a decentralized way.

In fact, it may well be the case that it is able to do these things in a more decentralized way than other cryptocurrencies such as Bitcoin, because no matter how collaborative an open source project might be, its development must ultimately have a central authority to lead the development. The ability to check whether code performs a required task may mean that Tau Chain users are able to propose and vote on features they want, put them out to tender, and validate any solution which is provided, all through the network itself without the need for a central authority.

Over time the network would build up a big library of pieces of code, each of which would have been proven to perform specific tasks. Eventually, it may even be able to combine these code fragments together itself to provide its own (artificially) intelligently designed computer programs.

In the same way, libraries of statements people have made, and whether they are true or false, might also be built up. This would allow the network to use the collective power of all its participants to answer ever more complex questions, and to embed the facts which it retains in an increasingly broad context, or meaning.

The first move Has just been made, upon my comment Ohad made a new rule, A rule that is not comply with the moderators rules, thus very soon the things that he  may allow to do on his thread are going to be against the rules of the moderators. Now, if anything that we do here is about demonstrating the content and essence of his platform and coin, thus it may be the most important part of  his thread. So we got a big conflict about to strike and since on the bitcoin forum the moderators have the upper hand, they can delete it all.

If this was on the blockchain, all the rules would be preset and my comments will be deleted even if Ohad wanted them to stay. On the blockchain to change a rule, he would have  to launch a 51% attack on the system and would have to have enough power to do so. (The thing we call democracy is in actual a 51% attack on our freedom as individuals) . But if this forum was set on the Tau-Chain a totally different thing would shape up: NO voting required (and most unwanted trolling will vanish). Once I will brake the rule Ohad will be able to accept it. if no one else oppose, it will change the blockchain to allow for comments categorized as "for delete" by the system  to stay on Ohads thread. He will in practice customized his thread. Now if my comment will offend Someone else that person will have the power to try and change it so the comment will be deleted.... but  let me actualy demonstrate a possible conflict here on another comment, since this is where it start to get really interesting and far more complex.

True, no coins yet, but soon in my plot I will present the point in which coins become very useful for the "game"of making rules to achieve maximum efficiency. And I believe that as you progress with the development of your platform, the perfect use of a coin will emerge. The stick and the carrot almost always work, unless you are a stick laughing at the carrot, but most of us are not HMC  

Published some notes and clarifications at http://www.idni.org/blog/post2

Some things are still not clear for me:

1) Will we be able to trade the tokens when the pre-sale ends?
2) How about having a bit more tranparency like reporting about sold/remaining coins and current price?
3) Any refund policy (if you don't reach the $2M goal)?

BTW, here are crowdsale best practices: https://github.com/DavidJohnstonCEO/CrowdsaleBestPractices

"About Tau-Chain" submitted to arXiv http://arxiv.org/abs/1502.04120
And, btw: http://primeurmagazine.com/weekly/AE-PR-03-15-83.html
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