I have several begonias that are excellent ever-blooming container plants. They do need protection from freezes,however. Many annuals are fantastic, free-blooming container plants, but need to be replaced a couple of times per year. I normally put several annuals in one container,making a colorful dish garden. I change them out as the seasons change. Since annuals are not very expensive, I find this a good way to keep color in my potted plants.
Molly

A friend gave me seeds of Dahlberg Daisy last year and it quickly became a favorite. It sat in a pot in full sun through last year's heat and never stopped blooming. Ferny foliage and pretty little yellow flowers. Supposedly it will freeze if we get a cold winter, but reseeds itself easily.

Gaura, Calylophus, Ruellia (invasive), Four O'clock (invasive)and Impatiens (annual).

Omar

Starry eyed nurembergia full sun and for a long long time it blooms.

passionvines do really well in pots. I just butt the pot next to a tree. I have also tried the claw plants from puerto rico, they are really doing well in pots, and show alot of new growth. All my plants do better in the ground, except for desert roses, they like it crowded. Barbra

Definitely impatiens, they do great on our shady front porch in hanging baskets, just keep them well watered.