A couple of weeks ago I installed the addon GTFO, and I highly recommend it if you are something of a spaz, like I am. The description is:
Alerts you when you're standing in stuff you're not supposed to be standing in.
I didn't have to configure anything. Whenever I am standing in say, fire, it makes a loud blaring sound that startles me, and I just start moving. Very cool imo.
[url=http://wow.curse.com/downloads/wow-addons/details/gtfo.aspx]GTFO Addon Link[/url]