American writers and journalists are always doing this. Do they really not know it makes the text unintelligible?

Even googling "A Lincoln" or "Lincoln" doesn't make it clear what they're trying to say, or how it applies.

When I read that I initially thought they meant the car company (Lincoln Motor Company), therefore I thought they were trying to say "if you spend car's worth of money you get <this>" except when you read on it is clear they didn't get enough value for that to make sense.

The short is: If you're a professional writer, blogger, journalist, or whatever and have an international audience, just stop it.

A 5 USD bill.

I was thinking a penny, but that makes so much more sense.

As far as I know, it's not something people say in real life, just a funny turn of phrase; "a Benjamin" is the only common use of a president's name for the denomination.

Friendly correction that Benjamin Franklin was not a president, your point stands though.

Hah! Something I even knew. Thanks for the correction. I guess we need to stop calling cash "dead presidents" [1] now.

[1] http://www.urbandictionary.com/define.php?term=dead+presiden...

I'd be willing to bet a Washington that no one in real life uses the term Lincoln.

Benjamin Franklin was never a President.