Rafflesia keithii (I think): one of the 17 known species of this parasitic flower which appears, without leaves or stems, from the roots of the liana vine. This is something of a holy grail for enthusiastic plant-hunters: so I'm feeling very, very privileged.
This was the only one flowering in Sabah, around the area of Poring Springs near Mt Kinabalu where there's one of the highest concentrations of these extremely rare plants: private garden owners make rich pickings when the flowers appear, but since it's not possible to transplant them or grow them from seed you have to be very, very lucky to have one appear in your garden. A bit like winning the botanical lottery.
They stink. There's no way of getting around it: Capt WE Johns, in his eminent tome 'Biggles in Borneo', refers to it as smelling of 'death and corruption'. Exactly so. Just think forgotten packet of mince left in the back of the fridge for a month or so.
It's pollinated by flies, of course: nothing with such a foul smell could be anything else.
The flowers start as swellings appearing like toadstools from the ground. It can take one of these swellings between 9 and 12 months to reach flowering stage (and not all of them get there): and then the flower lasts one week before it dies.
Did you ever see anything so redolent of putrefaction in your life?