For the legal entry, we always see cartoon characters writing them...
WILL
What Is Last Left
Writer Is LifeLess
Yeah, the second is pushing it, but it seemed to fit.
For trains, here are a few for different steam locomotive types:
MALLET
Massive Articulated Locomotive, Large Engineering Triumph
(The mallet type refers to any articulated steam locomotive; two sets of drive wheels under one boiler, with the front set on a pivot to get around turns easier; the design was first implemented by Anatole Mallet [ref: http://loggingmallets.railfan.net/sub/malletinfo.htm]
MOGUL
Mindful Of Gyrating, Uneven Lines
(the Mogul was one of the first wheel arrangements to include an unpowered axle before the drive axles; the unpowered axle helped guide the drive axles into a curve)
MASTODON
Massive And Stable-Treaded, One Design Over None
(The mastodon type, with two unpowered lead axles and four drive axles, was billed as the perfect answer to really heavy-duty hauling in the 1880s)
MOUNTAIN
Mastodon's Outdone Using New Trailing Axle, Improving Numbers
(the mountain type was a one-up of the mastodon by including a single unpowered trailing axle to support a larger firebox, giving the type even greater pulling power)
MIKADO
Made It, Kept Another Delivery Option
(The first locomotive of this type was built for export to Japan, to be delivered to the Mikado; however, WWII negated the delivery and all of the deliveries were redirected to US customers)
Finally, for dinos, how about...
PROTOCERATOPS
Prehistoric Relative Of Triceratops, One Chinese Excavation Reveals Another Treasure Of Prehistoric Science
(the protoceratops, considered to be a precursor of other horned dinos, was discovered in China and Mongolia; it is one of only a handful of creatures where scientists have found evidence from eggs through adulthood)