Good question, Toke.
The Nxt community spent (as usual) about 3 months arguing about whether appealing to 'dark markets' was a good thing or not.
Like it or not, dark markets were one of the main driving forces for BTC use and adoption, and are still one of the few completely solid usecases for crypto-currency.
The community feelings ran pretty high, but the consensus standpoint is that Nxt does not wish to support or endorse any illegal activity.
Getting specific on NXT functionality: yes,it is practical for a drug cartel to use NXT to sell and distribute their products, just like any legitimate business could.
Nxt has a native marketplace, and at least one good third party market app: FreeMarket.
Transactions on both can be completely anonymous and untraceable to a specific person, if they take basic precautions.
As a distro channel for naughty things, Nxt makes a lot of sense.
On moving/storing large quantities of cash: Nxt uses a brainwallet system, there are no local wallet files stored on a machine running Nxt.
This lack of a wallet could make life hard for any law enforcement agency who tries to seize NXT funds, and means that someone can carry large amounts of NXT stored in their brain, provided thay can commit their passphrase to memory.
There are a couple of issues, though, from the bad boy POV:
Nxt has a total market cap of just over $7,000,000 right now (
), and is , like all alts, still fairly illiquid.
Quickly transferring big piles of cash via Nxt, in the current market situation, won't be easy.
Nxt (like most crypto) is also completely transparent: all transactions can be traced. When it comes to genuine untraceability, paper money wins hands down.
The on/off ramps for NXT<>fiat are also a sticking point: if our hypothetical cartel is happy to hold only Nxt or other crypto-currencies, no problem, but if they want to convert Nxt to actual fiat, the on/off ramps are the obvious place for law enforcement to bust them.
The mixing service (Coin Shuffling) will be coming up with the following Nxt release, so lets see if the global drugs trade jumps onto Nxt then.
I don't think they will, and i'd prefer if they didn't........but who knows.
Summing it up: I can see a good usecase for Nxt as a dark market sales platform, but most of the Nxt community does not want to see dark market adoption.