I think it's safe to say I've never owned any of these. Of course, I've only been on this earth for the past 20 years, but hey, I managed to keep away from the actual ugly ones on this list. Like everyone else has been parrot-ing, there are some that don't belong here, and some that don't belong anywhere near here.

Some that do belong on this list though IMO are:

Suzuki X-90
Honda Element (although not hideous, a complete failure of styling)
Volkswagen "New Beetle" (I hate this car with a passion)
AMC Gremlin (this is just a novelty, c'mon)
Corbin Sparrow (what is this thing anyways?)
Pontiac Aztec (eww... it hurts my eyes...)
Almost forgot the PT Cruiser (why are these popular, or were popular? They're terrible aesthetically and mechanically)