A domain hack? That sounds like something a malware programmer would write to steal somebody’s website. Actually, a domain name hack is neither malicious nor illegal. A domain hack is an unconventional domain name that combines the top-level domain (TLD), to spell out the full "name" or title of the domain. Examples include del.icio.us, goo.gl and fold.it . In this context, the hack represents a trick (as in programming), not an exploit or break-in (as in security).
Domains such as .al, .as, .at, .in, .is, .it, .me, .us, or .co (Albania, American Samoa, Austria, India, Iceland, Italy, Montenegro, United States, or Colombia respectively) are easy to use as domain hacks because they correspond to short, simple dictionary words.
Domain hacks offer the ability to produce extremely short domain names. For example, blo.gs has a total of only five letters (versus blogs.com, at eight letters), as every letter is taken into account as the site's title.