Looking at the plant below, you'd be forgiven for, erm, stopping looking at it rather quickly. Not particularly attractive upright stems, big leaves, some sort of lily post deadheading perhaps? Not at all. This is one of the most sought after of all cycads; Ceratozamia euryphyllidia.
When it's not looking as sorry for itself as this one does this one is truly spectacular(and a lot of the other pictures online of the species looking spectacular are of this particular individual which on my day visiting it had obviously had a pruning for some horticultural reason - it'll grow back).
You can sort of see why in the above shot. That is my (as previously discussed average sized for a bloke) hand alongside some gigantic leaflets. Now imagine those arrayed either side of a 10 foot long leaf and you can imagine why this might be a desirable species to have. Unfortunately its yet another highly endangered plant. The wild population located in Veracruz, Mexico, apparently consists (or consisted of) around 30 plants. Whether any still exist I cannot say. There are rumours on the cycad grapevine that a single (shameful) collector now possesses a lot of (perhaps all) the wild specimens having collected from that population. They are not being pollinated and so the species remains critically endangered and rarely seen. In fact the above is the only specimen on public display I know of. Perhaps some day the collected population will get pollinated by someone and seeds will be spread across the world protecting the species. Perhaps not.