Twitter Monetizing Where to Find Content to Promote

I have seen a few of my Followers & Following Promoting these products.
I know for a fact it is not from MyLikes or SponsoredTweets.

So, what else is there out there?
Anything besides Mylikes & Sponsored Tweets?

BuySellAds, CPA, OPT-IN page with Freebies to build an email list.
How big is your following base?