Begonia blancii is native to the island of Palawan in the Philippines.  It is named after Patrick Blanc, the famous green wall builder and plant explorer.  The leaves are uniquely shaped for a Begonia, more paddle shaped, with rounded edges.  It grows on limestone insitu, and produces an abundance of flowers.  In cultivation, it seems to be almost always in bloom.  It can be acclimated to grow as a houseplant, at least in slightly more humid areas of the PNW (but very possibly lower ambient humidity as well).

The last photo is representative of the plants available.  They are well rooted and shipped meticulously in their pots.