There seems to be quite a few LEGO Train MOC popping up lately based on monstrous prototypes.
Union Pacific Big Boy by Jason Steinhurst
This is one of the nicest LEGO Big Boys I've seen.Great overall proportions, nice detailing and it uses the new Power Functions system for power.Check it out on Jasons Flickr page.
Shuppiluliumas has been busy
First he shows us that he's not afraid of tackling a Big Boy either. You can check out his excellent rendition here.
Then Shupp takes on the Union Pacific 9000 class 4-12-2
Yes you read that right. The UP 9000's had Twelve Drivers! Not only does this engine look nice but this rigid framed monster can take standard LEGO curves. And it just happens to also be powered with Power Functions. You can find Shupp's UP 9000 here.
And now Shupp is building an Erie P-1 Triplex. You can see his work in progress here.
Anthony Sava has been busy too.
First he unleashed his rendition of an Allegheny class 2-6-6-6 on an unsuspecting Brickworld audience. You can find his 10 wide monster here.
And now he has taken two of the new Emerald Night sets and kit bashed them into an impressive Emerald Garratt. And it's also using Power Functions. I'm seeing a pattern here proving just how versatile the new system can be.
And just so you don't think the only big engine were steam.
Swoofty's Union Pacific Turbine #68
This engine is so big you almost think it's 8 wide. But this monster is 6 wide showing just how massive the real Gas Turbines were. You can see more of #68 here.