Domain hack is not really my specialty as montsa007 do. I'm just a big fan of it
It is always nice to see these domain hack being registered and to be honest hacks are now getting some recognition from an end user.
For the hack to have value it has to be one word and short. buckshotdots is absolutely correct that it needs some marketing. However, there are some hacks that need no marketing specially the really catchy ones.
IMO hack would be more popular in coming years. Holding domain hacks can be very expensive but I am willing to take that chance. You can either develop it of park it to get some exposure.