Take this as a long term task but, as a sovereign nation, I think we should have our own currency too.
Ministry of Finance will sure agree we'll must have exchange rates to other world's currencies.

Even if it may sound strange, having an internal currency which is related to external ("normal") ones is not so hard task: someone did it even if not being a nation (look at SecondLife's "Linden dollar", L$, which is having exchange rates with USD and, thus, all other currencies in the world.
No need to say what we can do, with our currency: I'm not an economist but you may figure it easily.

I'll propose some names even:

1. Asgardia's crown: coming from Norse's actual currency, adapted to our Nation's name: the "crown".
2. Asgardia's Credit: a fair used Sci-Fi currency, the "credit".
3. Asgard: same as before but more compact name.
4. Solar: with XSL as currency symbol. @petrv proposal.

Currency code ISO-4217: XAS (https://en.wikipedia.org/wiki/ISO_4217) which is currently free to use.

All of this will hopefully be useful to develop internal commerce (eBanking) and finance.

Rare pepe trading cards

I like the simplicity of "Credit", but considering the amount the planet Earth owes (to....ummm someone), it may be better to call it "Debt" tokens.

Which leads to EyeRs' trading cards idea maybe being a good option in the long run.

Although they are a "legitimate form of currency", the submission of "rare pepe trading cards" wasn't intended to be taken seriously. Like the concept of "internal currency" itself, surely?

Pushing @petrv proposal one step forward: Sol ;-)
Now, @petrv, you've to find a viable acronym, as XAS fits for Asgard but not for Solar or Sol. ;-)

Updated! :-)

I think the marketplace for currency is already incredibly overcrowded.

I also think that an "internal currency" is going to be of no use in the short term. Whilst we generally exist on Earth, in other countries, the local currecny is a far more sensible solution. Trade almost always takes place in the local currency. In the long term, if we can realistically and sensibly think about mass habitiation of space, lots of things are going to require to change. One important thing is the concept of desperation. That cannot be allowed to occur or disasterous consequences will follow. Currency is a common tool to promote and to exploit desperations.

@petrv Sol rolled back to Solar :-)

@Mutyumu
It's not that difficult to set-up an internal currency: just to take a name (let's we say "asgard", XAS, for simplicity?) and let's say "you make the (useful) software application ABC, place it into Asgardia's MarketPlace (MP from now forward) and other asgardians can buy it for 100 XAS".

First problem here: if no one have any XAS into his (digital) wallet, how can anyone buy from MP?
Solution: let's say "each (certified) asgardian will receive 10.000 XAS into his/her own digital wallet, to start the internal economy"... how much is "10.000 XAS"? much? few? enough? it depends on the "(market) value" of the goods, so on the "exchange" we can think the XAS can have with other currencies on which our actual "value system" is based.
Let's say 1 € = 1.000 XAS, we can see we received 10 € "value" (or 10,72 $ at now), which seems "a few".

This is only a start, to place a base of reasoning: as we're thinking about an exchange (or "exchange rate") from XAS to €/$/whatever we're comparing "numbers" not "the value". Steps may be taken to officialize our internal currency and to create an exchange rate system in the exact way the SecondLife's Linden Dollar (L$) have an exchange rate with USD (and, thus, with all the other values 're having exchange rate with USD too), and SecondLife is not a Nation (it's a virtual world based into USA).

A step forward can be the one intended to "convert" (AKA buy/sell) international currencies into XAS, so that asgardians (but not only) can buy (or sell) goods via MP. This can also lead to make profit, by selling via MP (remembering there must be applied international taxes, e.g. VAT, to the transactions that must be taxed into the buyer's country). E.g. I can "invest" 100€, buying 100.000 XAS, so to have something in my wallet to (a) buy goods from MP, (b) pay Asgardia's taxes, (c) exchange XAS with asgardians' goods directly even, not via MP, etc.

So, we can see, to create an internal currency system and to relate it to external markets via the exchange rate is not that big burden.
All the transactions that will take place into "asgardian economic sphere" will happen electronically for sure (so that we won't need to coin physical money), so even international regulations on anti-money-laundering will be respected as transactions will be fully traceable even out of MP.
All the XAS an asgardian will earn will be directly expendable, if to pay something to another asgardian, MP or asgardian's taxes or services, or indirectly (after exchange) to pay other countries' goods. Let's say I have 100.000 XAS I can pay something which costs 100€ into EU (or 107,2$) by converting XAS/EUR (via PayPal for example).

The Asgardian Stock Exchange, allowing to buy or sell XAS into other currencies, will establish the "actual exchange ratio" exactly like other currencies' does.

@petrv
I´d say to set some kind of Asgardian National Bank instead of ASE...

Maybe we'll need both ones, I hope, at least. ;-)

@Mutyumu
I'm pretty sure things are more complicate than I explained with my little example: all I saw is an (internal) economic system in action, not it's creation.
What I can say is "it works", and it's not that complicate on how it works. It also handles real money, 'cause of international currencies' exchange ratio: I spend there, paying via PayPal, and I can earn also money from that system, via PayPal too (as a matter of fact I'm "balancing" my incomes with my shopping, there :-D).

We do not need any currency, we are gonna build a new society and we could be free from the error made in past. We could adopt a new kind of currency, the social points. Every work you make you will earn social pints to spend for your needs. Obviously asgardia as a nation must have a currency only for buy primary resources from the earth but that kind of currency must be used only for commercial relation between nations.

Hi Dario,

as I've told before, speaking of "points", "credits", "asgards", or "solars" is, at last, the same, as "1 point", in your post, will represent some kind of "work unit equivalence"... exactly the same as "1 asgard" (or "1 solar") will do.
As you'll end with some kind of currency anyway, why to adopt an "hidden currency" when you can adopt a real one?

You also recognized the need of a real currency for Asgardia/Earth's exchanges: why keeping the internal  (de facto) "currrency" separated from our external one?
I feel this separation may lead to some problems.

Definition of currency

plural currencies

1. 1a :  circulation as a medium of exchange
   b :  general use, acceptance, or prevalence a story gaining currency
   c :  the quality or state of being current :  currentness needed to check the accuracy andcurrency of the information
2. 2a :  something (as coins, treasury notes, and banknotes) that is in circulation as a medium of exchange
   b :  paper money in circulation
   c :  a common article for bartering Furs were once used as currency.
   d :  a medium of verbal or intellectual expression

.. From Merriam Webster

It doesn't matter what we call it, it's currency if we exchange it for things. 

I suppose you are talking about what one does to EARN this currency, citing social behavior. For those who are not particularly sociable, or charitable, or even nice, it removes them from the economy. Essentially, it sounds like a punishment for those who are not as sociable as others, which would be immoral.

When we have a constitutional draft out, I was going to write up an economic system (I have a degree which included finance and accounting and work in government accounting now, so I have a fair amount of expertise) and submit it as an official proposal. When that happens, I will be taking public commentary and input (not necessarily adding everything in, as that'd be a hellacious mess the way some speak).

YRO

Looking forward to read your document, @Phicksur. :-)

GLG