Surprisingly I couldn't find a good reference (like forum, wiki, blog post) to link to. But you can see it in the bitcoin source here: https://github.com/bitcoin/bitcoin/blob/master/src/core.h#L148
Code:
// "Dust" is defined in terms of CTransaction::nMinRelayTxFee,
// which has units satoshis-per-kilobyte.
// If you'd pay more than 1/3 in fees
// to spend something, then we consider it dust.
// A typical txout is 34 bytes big, and will
// need a CTxIn of at least 148 bytes to spend,
// so dust is a txout less than 54 uBTC
// (5460 satoshis) with default nMinRelayTxFee
Thats great, thank you very much
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Sadly, I had to add a house edge for the Multiply your BTC game as bots were bleeding it dry. It's currently at 5% but I will lower it if it exceeds break-even.
Bonus activated for those who posted.
