My favorite annual is dragon wing red begonia. It's like a begonia on steroids (hee, hee)
The hummers really love Cuphea David Verity and I love the hummers
Black and blue salvia, and Salvia 'Faye Chapelle', Elephant Ears, Caladiums
While they are all annuals in my zone 5b they can be overwintered and brought back out in late spring when it is consistantly 60 degrees at night. Saves big $$$$$$$