Slowloris HTTP DoS
Typical flooding attacks require tons and tons of packets and end up denying service to other applications as a result. By creating a flood of TCP requests, sure you can take down an upstream router, or a web server, but it’s overkill if you really just want to take down a single website. Slowloris does this without sending an overabundance of TCP or HTTP traffic, and it does so without increasing the load significantly, or in any other way hurting the box (assuming other things aren’t tied to the HTTP processes - like a database for instance). This appears to only affect certain types of webservers (generally those that thread processes, like Apache, but not like IIS).