Dioon rzedowskii. This is a medium-large sized cycad from southern Mexico and Central America. They have a very tropical look and are NOT one of the more hardy Dioons; that being said they are fairly hardy and can be grown in many temperate climates (with some protection). They prefer a partial sun-filtered light exposure, but can be grown in full sun coastally.
Chamaedorea ernesti-augusti. This is a dwarf palm that is cute as a bug's ear. They have a very large distribution throughout Belize, Guatemala, Honduras and Mexico. They are hardy and are an excellent filler plant in ANY tropical garden.
Encephalartos bandula. This is a Central African cycad type, which is fast growing, full and quite stunning as can be seen in the photo. They are very hard to come by, but are easy to grow in Mediterranean/chaparral to tropical climates.
Brahea pimo. This is a very rare and unusual Brahea (fan palm from Mexico, not to be confused with a "Mexican fan palm"). It is a smaller, slower growing palm, but they are quite tropical looking and are hardy to many climates. They do well in both sun and filtered light.
Encephalartos lehmanii. This is a stunning "blue" Encephalartos from South Africa. The are smaller plants and are medium growers (for cycads). I highly recommend this species to most people. It does well in tropical-temperate climates, but like most South African species, it prefers drier, hotter climates than wet and tropical.
Encephalartos horridus. This is a "blue" (plant speak for silvery plants) cycad from South Africa. Blue cycads are by far a customer favorite. There really aren't any plants which match the look of these.