You can now download the LOLspeak Translashun Dictionary, which provides Ruby code, a command line app and an OS X custom dictionary. It’s surely only a matter of time before someone produces a complete LOL-OS featuring feline-themed applications written in LOLCODE.

For anyone deranged enough to want a simple PHP option, feel free to use this crude translation code from the LOLinator (tweaked slightly to deal with plain text rather than markup):

function LOLtxt($txt)
{
 $txt = mb_strtolower($txt);  // or use strtolower()
 $txt = str_replace(array('great', 'some', 'your', 'text',
  '!', '?', ',', ':', 'ready', 'birth', 'christmas',
  'because', 'does', '$', 'million', 'billion', 'myspace',
  'youtube', 'facebook', 'apple', 'microsoft', 'google',
  'work', 'phone', 'ill', '&', 'about', 'home', 'blog',
  'navigation'), array('grate', 'sum', 'ur', 'txt',
  '!!?!', '??!', '...', '=', 'reddy', 'burf', 'xxxmass',
  'coz', 'do', '$$$', 'billian', 'zillian', 'meowspace',
  'mewtube', 'furbook', 'froot', 'milkysoft', 'gurgl',
  'wurk', 'fone', 'il', '+', 'bout', 'hoem', 'bl0g',
  'navigayshun'), $txt);
 return preg_replace(array('/\bone\b/', '/\btoo?\b/',
  '/\binto\b/', '/\b(yeah|yes)\b/', '/\b(hi|hello)\b/',
  '/\bhas\b/', '/\bhave\b/', '/\byou\b/', '/\bare\b/',
  '/\b(am|are)\b/', '/\b(was|were)\b/', '/ite\b/',
  '/ly\b/', '/ing\b/', '/\bis\b/', '/\bthe\b/',
  '/\band\b/', '/\bwith\b/', '/([rtpdg])s\b/',
  '/([klmnbvcei])s\b/', '/ck\b/', '/([^aeiou])er\b/',
  '/\bwhat\b/', '/though\b/', '/\bof\b/', '/est\b/',
  '/\boh\b/', '/\ban?\b/', '/ight\b/', '/\btime\b/',
  '/\bbe\b/', '/\bfor\b/', '/\bfrom\b/', '/ty\b/',
  '/(\'|’)(s|re|d|ve)\b/', '/[tc]ial(|ly)\b/', '/sign\b/',
  '/\b(doesn|won|shouldn|couldn|can|isn|wasn)(\'|’)t\b/',
  '/ted\b/', '/ive\b/', '/\bsays\b/', '/\bsaid\b/',
  '/(smile|laugh)/', '/\b(cat|kitten)(s?)\b/'), array('1',
  '2', 'in2', 'yep', 'hai', 'haz', 'has', 'u', 'r', 'is',
  'wuz', 'iet', 'li', 'in', 'iz', '', 'n', 'wit', '$1',
  '$1z', 'k', '$1a', 'wtf', 'tho', 'uv', 'es', 'o', '',
  'ite', 'tiem', 'b', '4', 'frm', 'tee', '', 'shl$1',
  'sine', 'not', 'td', 'iv', 'sez', 'sed', 'lol',
  'kitteh$2'), $txt);
}

Of course, the actual site also employs a crack team of trained kittens to frantically throw together wacky images and ugly page layouts with FrontPage 98.