Well you still need to get your IP to change and I don't think a firewall can do that (or maybe I'm wrong?).
You must still rely on either proxies or your ISP to change your IP.
The 20$ off 50$ order coupon I saw on that board was expired a while ago but several guys said they've seen some and that they were coming from the newsletter subscription thingie (needless to say I immediately subscribed 2 of my email addresses

)
Could a mod give me an answer on that coupon topic question?