I'm trying this build right now, and I'm having a blast
My char http://eu.battle.net/d3/en/profile/o...3/hero/7613795 (might not be updated)
Don't know if it's already been mentioned, but I'd recommend ik-boots and gloves as a way to lower the price a bit. Should be easy to find really good rolls for this build between 1-3M.
edit: I feel like I have to add a personal thanks to Windstriker, for struggling to get a working tempest rush build the last couple of months, so that I could just copy him and get it working in a couple of hours