[lojack]

ICO can mean any number of things, but typically refer to a token that is tied to something that isn't its own currency. I'm assuming the Filecoin is redeemable for data storage on their network, but I'm not super familiar with that technology specifically. To give some other examples...

Tether is a token tied to fiat currency

NEO Gas is used for compute time in their smart contracts. NEO also has a currency that is used to mine gas. It can be a little confusing, but one of them is a token and one is a coin. This is different than Ethereum, where the currency is also the token used to pay for compute time.

I can dig deeper and give examples of how some of the other tokens work, but unfortunately I'm not super familiar with the other tokens in the top 5.

And, yes, ICOs can be tied to some number of shares in a company. In these cases, the token is redeemable for a share of the company.

[elevensies]

Ok, so I think I can understand Tether. A token represents a share of a bank account balance. So the organization that controls Tether buys and sells the coins to keep the balances balanced. So the value of the token is predicated on the existence and continued support of the company. The on-blockchain nature is valued for transaction processing, and allowing it to be wired into other contracts (I presume), not for decentralization, because you have to trust the Tether organization, N=1. Otherwise Tether would just be a database and a website, backed up by some bank accounts, i.e. a bank.

Are you aware of any tokens that don't rely on some kind of managing external organization's voluntary continued support? Or at least anything run like an ETF, where someone can deliver a basket of assets and get them tokenized? Or the inverse?

[lojack]

NEO Gas is an example of this. Gas is a token that represents a fee that can be paid for executing the smart contract. Unlike Tether, when a smart contract is executed the Gas is consumed. NEO uses a consensus algorithm called proof of stake, so more NEO Gas is created using a coin (neo shares) which represent your stake in the consensus. In this case both the token (gas) and coin (share) have value, but the token can be redeemable for something -- smart contract execution.

Here's a list of fees associated with the token: http://docs.neo.org/en-us/sc/systemfees.html

[thisisit]

Well on Tether, refer to this: https://news.ycombinator.com/item?id=15482289

and the comments. Sorry I am not sure how to pull the comments to my post in the link.