Last year I got a fake CRKT Eat'n Tool that came in "real" packaging- I put that in quotes because the packaging was just as legitimate as the tool that came inside it. Upon comparing it with a real Eat'n Tool the differences were obvious, but if someone wasn't an enthusiast like I am, they could very easily be fooled into thinking they had something legitimate when they don't. Of course I'd informed CRKT of this at the time, but the sad reality is that there's not much that can be done to stem the flow of copies.
Basic copies are one thing, but to go the extra mile and put the company logo on the tool and package it as the real thing is an extremely dirty practice and despite me having purchased a few (mostly for these types of challenges) I really do not condone this behavior. I would even go so far as to suggest that any deal that seems too good to be true online may be a fake as well, no matter how legitimate it looks in person or in photos, and because of this you should always try to purchase from a legitimate, authorized dealer and use something along the lines of PayPal, which offers a buyer some protection.
The latest tool that seems to be going around in realistic looking packaging and with realistic looking markings is the Leatherman Mako Ti. Both myself (as part of the Five Dollar Challenge) and forum member Noa Isumi have recieved copies in very legitimate looking packaging. It would take a very trained eye to spot the slight difference in box color- the fake is a brighter yellow than traditional Leatherman packaging, and the fact that it is magnetic proves that it is not made from titanium and the "Ti" portion of the name would imply.
There are further details that set off alarm bells as well, such as improper screwdriver bits and a lower quality of polish, but none of these things are something you would be able to see in an online auction.
Chances are, if you are buying a brand name tool from a seller based in China for what appears to be an amazing price, you can be assured that you are indeed purchasing a fake, no matter how convincing it looks when it arrives. I would strongly advise against buying fakes for many reasons, but most importantly your personal safety.
Fakes are often made of thinner and/or lesser materials and do not undergo the rigorous testing and quality control that their actual, brand name counterparts do, and so may fail at a very inopportune time. Unlike a fake designer purse or fake watch, a tool is meant to be used, which means placing pressure on it. If it should fail, you could end up with a serious cut- or worse. While you can potentially save a few dollars by purchasing a fake over the original, I have to think that my fingers are more valuable than that.