Game 126: Oil's Well (1984), by John Rinck & Thomas Mitchell.
The world hungers for oil but getting the white globules it's contained in is dangerous work, Earth's subterranean creatures protect them fiercely.
The petroleum industry's solution? Put Pac Man on a big pipe and push him down the mines where he can freely eat both oil and creature, and retract the pipe when enemies come close to touching to it.
But don't forget that time is money so you need to work fast.
@loadhigh This ones a favorite of mine - especially the 1990 VGA remake.