Weaselhammer of Vector Sigma Creations is the very talented person behind this magnificent-looking replica of the M-12 Locust submachine gun from Mass Effect 2 and 3. The overall creation process took about three months, during which Weaselhammer crafted the model piece by piece, attaching synthetic polymer components to a wooden frame, and then giving it all a nice coat of paint.
You can take a look at some in progress pics below, read a summary of what went on at Weaselhammer's blog, or follow the project from its inception at Vector Sigma Creations' Facebook page.
Weaselhammer Props - Mass Effect M-12 Locust SMG
For comparison, here's what the original weapon looks like.