The majority of frame designs out there are human looking. Anthropomorphism is a strong force in creation and generally can only be overcome with intent.
First, here's the post over at Mechatonic that inspired this one.
Done? Good. Let's look at a handful that I find interesting.
The first three are all designed around the same look.
The next two are also similar.
This by FlamingMinister has a centauroid element mixed in.
And finally, the Crab Droid by The Solitary Dark.