You can save some money by inviting a friend to wow. he (well actually you) will get a 10day trial. You can do that up to 5 times. just go to the wow homepage, click on the ''invite a friend to wow'' button. Mail it to your own email. Follow the instructions in the mail and you are done.

Its good to try out Dual Boxing with this.

I do not recomend using a friends account since it is against Blizzard their policy and if they find out it leads to a permament Ban. So be carefull