I chose Zith, because there really aren't really any active Zith anymore.. :/
Also, I loved how their language can't be spoke by anyone other than another Zith - due to the physical limitations of a non-Zith vocal box. I loved how they adopt a name in Common, so others can address them, usually picking a word that represented something evil or unpleasant.. This kind of gave me a feeling of "superiority" per-say, in playing a Zith.
It worked out great because I had a word my mind had made up months ago (Shamelis was the word) and it just happened to have the word "Shame" in it! How perfect is that? So I built a back-story that would incorporate the minuscule society Zith usually live in, and a reason for my character to hold "shame" within them as a character flaw!
Oh.. but I almost forgot.. the two selling points for me on the race of Zith...
Zith can hear heartbeats - AND fly. How awesome is that?!?!