There's one from Brians Botanicals called Colocasia Hardy pink china that is super hardy., and maybe check out some of the larger Petasites species that are similar, but more hardy. There are also quite a few palm trees that are hardy when they get to a good size, like some Trachycarpus, Sabal, Rhyphidoplyllum hystrix, Butia(a species or 2). Like Chong said Hedychicum is a nice tropical, and H.'Tara' is and awesome hardy one. Once you get into trees there are quite a few that have a tropical look.
And then there is bamboo, definatly check out timber bamboos, Phyllostachys vivax 'Huangwenzhu Inversa' would be a nice one(bottom right corner of page).
Timber Bamboo