A caterpillar-tracked earthmover.    From Wordnet, Princeton University. 

In a delightful caterpillar-tracked U-Turn Blair and his comrades have decided to donate 25% of the 79p proceeds per download to Stop The War.    From Wordnik.com.  [Archive 2006-12-24] Reference

Anyway, I promised Jeff I would photograph the novel in a typical steam-powered environment and so I jumped into my road-going vaporetto it's like the Venice type taxis but I've converted it to caterpillar-tracked locomotion so it's multi-terrain and made my way down to Swansea's Industrial Museum and took a few photos, here they are.    From Wordnik.com.  [Archive 2008-05-01] Reference

"We are here to stop them attacking the machines," says the major, pointing to the big caterpillar-tracked diggers that are breaking up rock for the wall's foundations in the dry little valley just beneath his position.    From Wordnik.com.  [Palestine Blogs aggregator] Reference

A caterpillar-tracked excavator will cut trenches in the tailing mounds left over from the former Beauce Placer Gold mining operation of 1960 to 1961. 20 channel samples will be analyzed for gold at the CTMP by gravimetric methods.    From Wordnik.com.  [Marketwire - Breaking News Releases] Reference

After reacquainting the player with the game's stalwart cover-heavy gunplay, Gears 2 sees Marcus and Dom take the fight to the Locust - guarding a series of lumbering, caterpillar-tracked derricks as they make their way into the snow-bound countryside to where they hope to drill down into the enemy hive.    From Wordnik.com.  [Edge Online - Interactive Entertainment Today] Reference