I've been sitting here for 30 minutes trying fruitlessly to find the words to open up this discussion about currency in games. So, yeah, currency in games are cool and weird to think about. How's that? Let's get into the meat of things already.
There are a myriad of ways that games portray currency in games. In some games, currency is merely the fuel that keeps the game going, in other games, currency is the filler between item 1 and item 2. And then there are games, where currency is just another collectible, a less valuable one at that. It's interesting to think about, because most games' view on currency completely juxtapose the "real" view on currency. Here in reality, cash is king. With it you buy shelter and food. It's something we spend the majority of our lives acquiring, only to spend it on things that allow us to keep going. Few games, outside of really hardcore survivalist games, really use currency in a "realistic" fashion. That is probably because the game would become tedious really quickly if your level 75 hero of the universe had to grind up gold to pay rent. But let's look at some different ways currency exist in games.
One of the weirdest genres to handle currency must be the hack 'n' slash/action-RPG genre. In for example Diablo or Torchlight, you kill monsters, loot their stuff and gold, sell all the useless stuff and purchase better pants for yourself. The entire economy in any gives game like this hinges on one character going out and looting the corpses of endlessly respawning mooks. Most vendors in these games even look like fences or pawn-shops. You won't find many vendors who carry any form of unified stock. No one has a dozen short swords of identical make and brand. Everything is looted and put in pile for you to sift through. This is fine, in game standard, but brakes completely when thought about. Why is there a kingdom (under attack by demons) whose entire economy is based around re-selling swords looted from demons? The obvious answer would be that the game only shows the player the essential parts of the world. We are only privy to what goes down in the front, or in the theater of war. We never get to see the industry behind the world or the way that regular folks live. But it is still a weird place to be, if the most commonly traded commodities are things stolen from dead enemies. This looters paradise also makes the actual currency in these games broken. For example, gold in diablo only serves as means of repairing existing gear and acquiring new gear. It has no other use for the character. And since it's a endlessly regenerating resource (you can just "farm" gold by killing enemies) it lacks any virtual value. How much is the rent for the shop in act 2 of Diablo 3? Is it 1000 gold? It it 10.000? Would it not be more expedient for the shop-keeper to just take the looted gear he owns and set out on the battlefield himself? Maybe the monsters are too strong? Why can't he hire some muscle? How much would that cost?
Other games value currency a bit more. Armored Core 4 comes to mind. In AC4, you earn currency by going on missions. But you are also deducted pay from your salary to repair any damage you took and pay for ammunition spent. This is an interesting idea, since it can actually cost you going on missions, instead of just paying off. This makes currency much more precious, since you stand to loose it if you play poorly. Now, the system ins't perfect, but it still makes more sense than most. In AC4, currency gained from missions is used to upgrade your core (AC term for "mech", in other words, a giant robot) and insulate you from poor play. You can go on a mission "risk-free" by having enough cash to back up any damage and ammunition spent. However, doing so might exclude you from buying better stuff down the road. So, here money has context. It's not just fuel for gear, it is also something that has to be used to cover expenses. You have to have money to make money, and you have to spend money to make money.
Now you're probably thinking that it's unfair for me to compare Diablo to Armored Core, since they're two very different games in two very different genres. It's true, it is unfair. But this article is not about chastising games like Diablo, it's simple to highlight the strange ways some games use currency.
Another simple example would be Monster Hunter for the 3DS. It's a total grind-fest where you grind for material and cash to make and upgrade equipment. Pretty similar to Diablo. The main difference here is that in Monster Hunter, most missions have an entry fee. You can't go out hunting if you can't front the bill. The fee is usually tiny and I would bet that most people don't think about it. But this key difference puts the currency in monster hunter in a greater context. It, again, isn't JUST fuel for gear and items.
Value and amount are also interesting things when it comes to currency in games. For example, in the new XCOM your currency is §, let's call it "credits" for simplicity. The interesting thing here is the value and amount. The cost of Power Generator in the game is 60 credits. For context, this is a room sized Power Generator, installed in a under-ground complex, that is able to power several room-sized facilities. So, what would the exchange rate of credits to dollars be? I imagine quite the bit. Since I would estimate that building and installing such a facility would be quite costly. But in the game, it's only "60§", which at first glance seems like an amount that could be stored in your wallet. To go a little deeper, a standard recruit in the game costs 10§. While they're not very good (in game standards), they still represent some of the best and brightest the world has to offer, but the cost is still 10. A number so small in average currency discussion that it would fit on a coin.
On the flip side of this, Disgaea. In Disgaea you earn HL(hell). Again, it's a regenerating resource, so just go farm some. It starts off having no real value, but it goes ludicrously over-board very quickly. Because in Disgaea, you can earn this currency hand over fist very easily. So after only a couple of hours of play, you will will be earning HL in the millions. This is for balancing purposes, since the game is all about grinding and making strong characters. But it still feels weird when the first weapon yo buy in the game costs 100 HL and a weapon you buy just a couple of hours later costs over a million HL. Truly, the netherworld economy is broken to the point of non-existence.