Waterworld
While there's no denying this movie always leaves me feeling like it's nowhere near as good as it could/should have been, in today's age of ubiquitous CGI-fests the sheer scale of practical moviemaking on display here is simply staggering to behold. Even many of the more rudimentary scenes are impressive, but the atoll attack sequence in particular is just mental.
I mean, sure, there's a ton of stuff in this that makes absolutely no sense (why the f**k would dirt be the world's most valuable currency?) but you can't say it's not memorable.
(I watched this on my recently acquired Arrow Blu-ray, so at some point in the not too distant future I plan on checking out the extended cut, which I've never seen.)