Robotic conveyances like the BigDog attest to the advances that biomimetic beings have made in recent years. But the walking machines of today lack that sinister je ne sais quoi of old-school robots, namely Odetics' ODEX series of insectoid walkers.
The creators of this experimental walker envisioned using it for battlefield applications and braving the radioactive areas of nuclear power plants. Although it wasn't the zippiest robot around, the 300-pound ODEX-1 could carry 900 pounds while walking normally.
Even though these particular ODEX models never saw widespread usage, during their heyday they were presumably used for many a pants-soiling office prank and press conferences in the Omni Consumer Products mold (that were decidedly less ill-fated).