This could be your new website address! at.ac is a premium domain name, being released from an allocation of domains that were previously unavailable for registration.
In a world of long domain names, a premium, short and memorable domain name is a very attractive URL for a website or email. They are easier to remember, faster to type, and are bold, distinctive ways to stand out from the rest of the crowd.
These domains are becoming available as part of an historic process where the registry is relaxing its prior restrictions regarding allocation of this and other domains.