As of 1pm GMT on 8/26/12 and continuing through now, HackThisSite has been continually experiencing an extremely large Distributed Denial of Service (DDoS) attack against its servers. This ongoing attack has varied in size and type, ranging from about a dozen Mbps to several Gpbs in size, and anything from standard SYN floods to layer-7 (Application layer) HTTP request attacks.
Normally, HackThisSite receives multiple DDoS attacks per month (upwards of several hundred), but our hosting provider as well as our own in-house systems are capable of mitigating these attacks with little to no human intervention. However, due to the scale and complexity of this current attack, we are able to mostly mitigate the damage, but this is rendering some portions of HackThisSite inoperable for many users, namely the website where the vast majority of the attacks are occurring. We will continue to tune our firewall systems as the attacks persist.
To the attackers, however, we have only this to say: Really? A DDoS? Grow a pair.