Sabretooth, a member of Figure Realm, has the whole custom toy thing down! Whether its making a toy from scratch from bits and pieces, or just customising other toys.
This figurine, from the movie District 9 was built from a Transformers Thundercracker 2007 movie toy, half of a broken Lego Bionicle, some chopsticks, sheet plastic, paint and "a lot of time and patience." He stands approximately 3 3/4" tall and is highly poseable.
This Optimus Prime figurine was repainted using Tamiya acrylics and some weathering techinques. As for his gun it was scratch built out of pieces.
This is the Big Daddy character from the game Bioshock. He started off as a Kingpin Faceoff Marvel Legend and through about a weeks worth of toil and trouble and a pack of leds here's the end result. The wire guard around his head is actual wire, and there are 8 leds in his head. All the detail work was hand sculpted. The drill was made from scratch, using alot of magic sculpt.