The giant, mutant-killing robots in the latest X-Men movie didn't look exactly like they do in Marvel Comics' popular superhero series. They were still recognizable as Sentinels, though. Alternate designs would've had them look almost like human beings.
A post up at Slashfilm reveals that both the Sentinels from the past and future eras of the newest X-Men film went through a few different iterations. Design studio Framestore contributed to Days of Future Past and worked up radically different looks for the fearsome mechanical menaces that Wolverine and crew have to take on. Some of the looks invoke Japanese mecha styling. Others look a lot more amorphous and organic, with a slightly feminine silhouette that recalls X-Men arch-villain Mystique. I really hope those mecha designs show up in an alternate reality somewhere.