Lego

Of all the toys that many of us have played with, there is one that stands out above all as clearly superior: the Lego brick. Lego bricks are strong and durable, and the possibilities for what can be built are almost limitless. But Legos aren't just for for kids anymore. over the past fifteen or so years a small community of dedicated adult builders around the world have gone above and beyond the "rainbow warrior" and created an art form. Over at the Brothers Brick, they display fantastically detailed models and creations so lifelike you will think that the thumbnail is the real thing. These MOCs (my own creation) can take days to months to build, and can be a few inchs long, or a few feet. It all depends on the builder.
Unfortunately, there have been some recent deaths in the community, that of renowned builder Nathan "Nnenn" Neilson, and Daniel Jezek, the founder of Bricklink (the primary website for bulk Lego purchases). They were both extremely influential in shaping the hobby into what it is today, and will be missed. Nathan in particular, was responsible for the Vic Viper, a special format of spacecraft that he made widely popular around the world. A space builder's portfolio is not considered complete until he has built a Vic Viper.
Recently, The british ship builder Ed Dimmet, Under the screenname "Lego monster" built a fully acurate, 23 foot long model of the USS Intrepid, a WWII aircraft carrier. The build required five people to complete, and could not be assembled in his house, as it would not fit. His wife built all  of the ship's full complement of aircraft, some of which reside inside the fullly detailed interior of the ship. In the Lego world this is known as a SHIP, or Seriously Huge Investment in Parts. Interestingly enough, it is not the world's largest lego boat. That title currently belongs to the Yamato, a Japanese battleship that took six years to build.
-Jts

*Sorry about the lack of photos, but most builders do not use CC licences for fear of image theft during build contests.