Aristolochia platensis (the Darth Vader Flower)

The Darth Vader flower, also known as Aristolochia salvador platensis [is that A. slvador var/f/subsp platensis?]

Aristolochia gigantia (Pelican Flower)

The spectacular Aristolochia gigantia is flowering now in the Princess of Wales Conservatory at Kew Gardens and it's bigger and better than ever! The huge, spectacular display is not to be missed. Watch out though - it gets a bit pongy in the afternoons! Find out about visiting Kew here: http://on.fb.me/14LpX8x — The spectacular (and a bit smelly) Aristolochia gigantia! (3 photos)

Other plants for the (Proposed) Cabinet of Botanical Curiosities

This list is from the post I did some time ago on Talking Plants, just to keep these ideas in the same place as the others.

Big ones
Amorphophallus titanum; Rafflesia sp.; Victoria amazonica/cruziana; largest orchid, cactus etc. flower; fungi (basidiomycetes)...
Also Aristolochia gigantia (Pelican Flower).

Little ones

Wolfsia; Nymphaea thermarum (alongside Victoria); smallest orchid flower; cryptogams (models of algae/desmid, fungi and bryophytes)...

Fast ones

Stylidium (Trigger plant; also stilt plants from WA); moss capsule; that Cornus that does something interesting...

Others

Welwitschia mirabilis; Dracena draco (Dragon-blood Tree); Jade vine (vivid blue-green flowers); carnivorous plants, odd cacti and succulents...