I've never heard of signature campaigns before. Is this something specific to Bitcoin Talk, or is it something that happens in all types of forums?
If you want to earn a lot of Bitcoin from just faucets then forget about it. Faucets will not make you rich. Instead, you should focus on ranking up your Bitcointalk account. With a good Bitcointalk account, you will be able to participate in high paying signature campaign. What's signature campaign, you ask? Basically, you rent out your forum's signature space (right below every posts you make) to people.
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Signature campaign is a term used in Bitcointalk. There is of course a few other forums that have similar things to signature campaign - where you rent out your signature. As far as payout and popularity, Bitcointalk is one of the biggest out there - or probably the giant forums for signature campaign. More importantly is that most signature campaign payout in Bitcoin.
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