Benjamin in Crosstime Traffic
A benjamin (lower case) was the unofficial name for a hundred dollars in the currency of the United States in the home timeline, which had gone through a period of hyperinflation. A single dollar was a nearly worthless aluminum coin; even a benjamin was not worth very much, not even enough to pay for a single bus fare.
While the name was widely used in spoken language, it had no official status, and formally the Dollar remained the sole unit of US currency. Thus, while people going to a movie would normally speak of the price being "eight benjamins", the sign at the entrance would say "800 Dollars".
The benjamin came in both paper form and coin form. The coin form was colored brass-yellow. Its obverse depicted the face of Benjamin Franklin with the word LIBERTY above his head, the words "IN GOD WE TRUST" to one side of him, and the date and mint initial to the other side. The reverse showed a bald eagle, the words "United States of America", and in smaller characters "E Pluribus Unum", "One Hundred Dollars" and the date.
The Euro had gone through a similar process of hyperinflation. Europeans tended to speak of a hundred Euros as "A Big One" in whatever language they were speaking, the equivalent of the American benjamin.
Benjamin in The Disunited States of America
When Justin Monroe said goodbye to Beckie Royer, he gave her an envelope and asked her to open it only after getting back to California. He said it would offer a partial explanation of his background. After Beckie went through quarantine in Ohio and then California, she had almost forgotten about it. But she remembered and opened the envelop in the privacy of her bedroom. She found inside a coin - a daily commonplace in Justin's timeline but the most strange of curiosities in hers. The brass-yellow coin, unlike any of those which Beckie saw from various parts of North America, had on the obverse the bust of Benjamin Franklin. Above his head was written LIBERTY, on one side of his bust the words "IN GOD WE TRUST" and on the other side the date 2091 and a small capital P. On the reverse was the design of a Bald Eagle, the words "United States of America", and in smaller characters "E Pluribus Unum", "One Hundred Dollars" and the date 2091.
Benjamin in The Valley-Westside War
Before Liz Mendoza went to an alternate where a nuclear war set civilization back, she had to learn about pennies, nickles, dimes and quarters which were still in use there. She found that a a penny there would buy more than what a dollar would buy in the home timeline and that a benjamin would be valued at somewhere between a dime and quater.