Although this isn't an effective tool for websites that actually sell something, a community I was part of a few years ago was experiencing a very malicious and

Although this isn't an effective tool for websites that actually sell something, a community I was part of a few years ago was experiencing a very malicious and heavy DDOS for almost 30 hours, so during 2AM CST they set their DNS to forward their domain name to 127.0.0.1. The attackers ended up DDOSing themselves. When they set the DNS back properly, for some reason the attackers had stopped. I guess they felt too ashamed to try again! EDIT: It might also be possible, of course, to blacklist certain IPs and force those to be redirected to their localhost.