Fresh install of Ubuntu Server 12.04 LTS: After installed SSHD, I found that logging in remotely was a time-consuming process as the password prompt took ages to pop up after the username prompt. Binging about, I found that this was due to SSHD performing a reverse DNS lookup of my IP to potentially check if all is kosher. Turning this check off fixes the issue:
If you manage websites that involve user registrations, I'm sure you have come across users who use services such as mailinator to register. While these services are definitely handy, the users who use them generally tend to be spammers or those that don't necessarily plan to stay on at your website. The following is a list of sites / services / domains that provide services similar to mailinator, and have found their way into my block list.