Usually asked at the end of a long, boring and drawn out story to give it a more interesting and rewarding ending.

Sarcastic in nature.

Alternately used in place of "and then I found five dollars" because finding twenty dollars is rewarding enough while still being in the parameters of seeming like you really found something. Saying "and then I found one hundred dollars" sounds too fake and thus brings down the sarcastic tone you're trying to get across to the person because their story was so boring. Finding anything less than twenty dollars isn't really that rewarding.
Person A: So the other day I ordered these couches online and had them delivered on Saturday. In the pictures online they looked like a nice tan color but when they get to my house they are a mustard yellow color. So I told the company I didn't want them and to come pick them back up. So the next day I go the furniture store near me and found couches I liked better so I bought them and had them delivered on Tuesday. However, the guys from the other store never came to pick up the mustard yellow couches. So now I got four couches sitting in my living room. I was so pissed I got up and walked to the beach to cool myself off.

Person A: And then you found twenty dollars?
by CobraKaiNeverDies February 12, 2007
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