using DynDNS with AWS

So, let's say you have an AWS instance that you don't run all the time, and you get a new IP each time you run it.

Sign up for an account on DynDNS and install the ddclient on your instance.
ddclient.conf example

syslog=yes # log update msgs to syslog
mail=root # mail all msgs to root
mail-failure=root # mail failed update msgs to root
pid=/var/run/ddclient.pid # record PID in file.
ssl=yes # use ssl-support. Works with
login=dyndnsusername
password=dyndnspassword
protocol=dyndns2
server=members.dyndns.org
dyndnshostname.dyndnsdomain.dyndnstld, anotherdyndnshostname.dyndnsdomain.dyndnstld
use=web
web=checkip.dyndns.org

now each time you start the service, you can go to the dyndns account instead of trying to figure out the new IP address/dns