They think about Western Union is you can recieve funds without so much as providing your name and a transaction #, so no paper trail is left, aside from the wad of cash you made off with, a few singles blowing off the stack here and there. This is why scam artists like Western Union. In fact scams are how Western Union gets most of its business (note the disclaimer on Craigslist which specifically warns against using Western Union).
A great online scam involves the following: a few individuals feigning to represent a "Money Transfering" business, a stolen credit card, and a schmuck who agrees to accept a questionable sum of cash via Paypal, transfer it to a personal bank account (effectively laundering the funds), and send it via Western Union to a designated recipient for a nominal fee. That's one lesson you can learn the hard way (a lifelong ban from Paypal and endless, harrassing phone calls from various debt collectors later).
Sometimes you can be scammed out of more than just you money. For instance, your time and work; there are all sorts of devious employers out there (in the world of freelance anyway), who swindle unsuspecting individuals out of work they've performed, per agreement, without proper compensation. This is incredibly corrupt and disgusting. For a writer, at any rate, to part with a piece a work without even being given credit is criminal (it's called plagiarism), and to not be paid is a slap in the face to add to a partial decapitation. Ways to be sure this doesn't happen is to agree to a trial or provide a small sample to be sure that money is not in fact a problem. If ever the employer gets uncomfortable or becomes undependable on all matter money-related, the appropriate response is to be completely resistant towards (or at least hesitant of) collaborating any further.
The thing about Gmail (or Yahoo Mail) is, anyone can create an account (or a thousand) for free without so much as disclosing a drop of personal information. In that way no one, criminal or otherwise, can be linked or uncovered via an email handle as generic as JoeSmith@gmail.com or AGoodGuy@yahoo.com. And as soon as one plot has been foiled, it is impossible easy to through the handle in the river free of prints and create another one. Might I suggest JoeSmith1@gmail.com.
There are a lot of cyber-Bonnie and Clydes out there, romantic partners in crime who have accepted their lack of morals and might even get off on pulling a fast one on some unwitting dupe. And that unwitting individual is in fact a dupe if he decides to entrust a large some of money with a pair of strangers, rather than a reputable institution, without any kind of preliminary background check (if that's even an option). Sometimes failing to do your homework can result in the bully stealing all your lunch money.
Anybody who's in a big hurry to get into your pants (your wallet that is), should be questioned. To relinquish a large some of money is a lot like handing out your sex. You have to know a little more about the recipient, in particular what you are getting in return. If this person is too impatient for necessary chit-chat and for all the steps leading up the the ultimate transaciton, then what you have is a poor choice of candidates. And one that will likely leave you crying and unfulfilled in the corner of your bedroom. Beware of giving out your digits to just anyone (your credit card digits that is).
This has to be the greatest sleight-of-hand of them all, and the most ironic one (as deceipt is considered the most Satan-like of sins): some scammers will play up a deep devotion to Christianity, so as to make their sense of "morality" implied upfront, making implications otherwise completely unthinkable. The idea is to instill a sense of trust by using a universal symbol of "goodness" to disarm any suspicions straight off the bat. In essence, God is prostituted to make a seedy transaction by the absolutely most dishonest means possible. If Hell does exist, there is a velvet rope in the lowest circle marking the entrance to a VIP section, reserved for no one but these scamming specialists.
Most legitimate transactors (apartment renters, merchandise vendors, etc.) will gladly meet in person to make the exchange, if just to sustantiate the validity of what is being offered. An apartment, more than anything, should be shown off to the potential renter prior to arranging for deposits and rental agreements. But there are tricksters out there who having nothing tangible to actually provide, discounting a few JPGs, and think their living in another country is excuse enough to put absolute confidence in their words alone. Main point to walk away with: never deal non-locally when using one-on-one services like Craigslist (whereas Ebay, Amazon, and Paypal operate like negotiators, making sure both parties get their dues).
Here's something fishy: when you are about to make a transaction, and you are instructed to send your payment to a name or affiliate other than the party that you are supposedly dealing with directly. This third party can very well be a buffer or laundering mechanism so no direct ties can be traced from the scene of the crime. Think of it like The Godfather, where in which the Don always uses a middle man to order the hits so that no incriminating connections can be made. Keep an eye out for this next time you are made an "offer you can't refuse."
When it comes to the appriation of funds, and particularly large amounts, clarity of communication is essential. You can't afford to not be absolutely certain of what's taking place in a given transaction. Whether it's by a poor grasp on English, or a purposely murky and ambiguous use of language, you have to be sure you are going to get what you are paying for or working towards. If need be, this might require a written, legally-binding contract-of-sorts to make sure there is an emphatic "or else" to accompany your "give me this." If nothing can be guaranteed, best to just walk away and save yourself the devestating risk.
The old saying is "If it sounds too good to be true, it probably is." And there is great truth in the aphorism. All over (Craigslist mostly), there are (falllacious) promises of $500 studio apartments sitting in the heart of a major city, waiting for some "lucky" recipient. Or maybe there is tell of some rare collectible record album for sale at an incrdibly decent price (in South America), and all you need do is send the money upfront. These things are all too good to be true. We just don't live in that good of a world, where everything is located on the lowest shelf. Most things involve frustrating struggle and painstaking acquisition. Welcome to the world we live in.