[cwkoss]

Seems like you can just pre-announce any information source you do not control and then take hash mod 20 once the content is made available.

Ex.

- Next article title posted on NYT

- Donald Trumps next tweet

- Sum of tomorrow's lottery numbers, mod 20

[viperscape]

But that means waiting for the third party right?

[TJSomething]

You can use publicly available data feeds that changes every few minutes. For example, CNN's Afterhours trading data [0] seems to work pretty well. And it's just HTML, so you just hash it and you're good.

[0] http://money.cnn.com/data/afterhours/