NCR dollar

The NCR dollar, or simply money in Fallout 2 and Fallout: New Vegas, is the official currency of the New California Republic.

Background
The NCR introduced its own money around the turn of the 22nd century and initially it relied on coins minted from gold. By 2241, the economy of NCR dominated the West Coast and coins became universal currency, used by the three regional powers: NCR, Vault City and New Reno. During this time bottle caps had become worthless in these regions. 

During the conflict with the Brotherhood the Republic's gold reserves were destroyed by Brotherhood raids to the point where new gold coins could not be minted and paper money could not be properly backed with gold. NCR citizens panicked and rushed to reclaim the listed face value of currency from NCR's remaining gold reserves. Since the NCR was unable to realize these withdrawals, particularly towards the frontier, faith in their currency considerably dropped. To protect against actual economic collapse, the NCR government abandoned the gold standard and established fiat currency, not payable in specie. Since then many wastelanders lost faith in it as a medium of worth, both as a result of it not being backed by anything but the government's word and the inevitable inflation. In response to the loss of faith, merchant consortiums of the Hub re-established their own currency, the veritable bottle cap, backing it with water (exchanging a standardized measure of water for caps). "It happened during the BoS-NCR war. I believe Alice McLafferty mentions it, but I'm not positive. She doesn't detail the events in this much detail, but here they are:

The attacks caused NCR citizens (and others who held NCR currency) to panic, resulting in a rush to reclaim the listed face value of currency from NCR's gold reserves. Inability to do this at several locations (especially near the periphery of NCR territory where reserves were normally low) caused a loss of faith in NCR's ability to back their currency.

Though NCR eventually stopped the BoS attacks, they decided to protect against future problems by switching to fiat currency. While this meant that BoS could no longer attack a) reserves or b) the source of production (all NCR bills are made in the Boneyard), some people felt more uneasy about their money not having any "real" (backed) value. This loss of confidence increased with NCR inflation, an ever-looming spectre of fiat currency.

Because the Hub links NCR with the Mojave Wasteland and beyond, the merchants there grew frustrated with NCR's handling of the currency crisis. They conspired to re-introduce the bottle cap as a water-backed currency that could "bridge the gap" between NCR and Legion territory. In the time leading up to the re-introduction, they did the footwork to position themselves properly. If some old-timer had a chest full of caps, they didn't care (in fact, they thought that was great, since the old-timers would enthusiastically embrace the return of the cap), but they did seek to control or destroy production facilities and truly large volumes of caps (e.g. Typhon's treasure) whenever possible." --J.E. Sawyer, src

By 2281, the NCR dollar is valued at about 40% of a water-backed cap and only 10% of a silver Legion denarius. In the Mojave Wasteland, these notes can be seen in the $5, $20, and $100 denominations. The notes are issued by the Republic Reserve Bank located in Angel's Boneyard. In 2281, the current Treasurer of the Republic and head of the NCR Treasury is John Michael Henderton; his signature can be found on the front face of all NCR notes found in the Mojave Wasteland.

Cents
Sub-$1 denominations are used by the Republic, but do not appear in any of the released games for gameplay reasons.

$1


$1 appears as a gold coin similar to US dollar coins. It is also circulated as a bill, but it does not appear in any games as an item for gameplay reasons.

$5


$5 appears as a paper bill similar to a US $5 bill. It features a portrait of Aradesh on the face of the bill and a landscape image of the Shady Sands well on the back.

$20


$20 appears as a paper bill similar to a US $20 bill. It features a portrait of First Ranger Seth on the face of the bill and two pieces of New California Ranger insignias on the back.

$100


$100 appears as a paper bill similar to a US $100 bill. It features a portrait of President Tandi on the face of the bill, and an image of Tandi addressing a crowd at Dayglow on the back.

$500
When post-endgame play for Fallout: New Vegas was being considered, J.E. Sawyer intended to have NCR release a commemorative $500 bill depicting President Aaron Kimball or Chief Hanlon in the event of NCR victory at the dam.