Terry Pratchett, the author of the Discworld novels, has been knighted in the New Year's honours list.
The 60-year-old, who was diagnosed with early-onset Alzheimer's disease in 2007, said he was "flabbergasted" to receive the knighthood for his services to literature.
Led Zeppelin frontman Robert Plant, actor Michael Sheen and jazz musician Courtney Pine were also among the entertainment figures honoured.
"There are times when phrases such as 'totally astonished' just don't do the job," said Sir Terry of his knighthood.
"I am of course delighted and honoured and, needless to say, flabbergasted."
Sir Terry has sold more than 55 million copies of his Discworld novels, set in a fantasy world balanced on the backs of four elephants standing on the back of a giant turtle.
Since being diagnosed with Alzheimer's, Sir Terry has campaigned tirelessly for greater research into the brain disorder, donating $1 million (£494,000) to the Alzheimer's Research Trust and meeting with the prime minister to request more funding for dementia studies.
Neil Hunt, chief executive of the Alzheimer's Society, said: "I would like to congratulate Terry on this fantastic and well-deserved achievement.
"Terry is not only a successful author and well-loved public figure; he is also playing a key role in fighting the misunderstanding and stigma surrounding dementia."
Plant and saxophonist Pine were both named CBEs, with Sheen an OBE and former BBC radio head Jenny Abramsky made a dame.
Sheen, soon to be seen in political drama Frost/Nixon, said being included in the list was a "huge honour".
"I am both thrilled and slightly mystified. But very grateful. It'll be nice to meet the real Queen at last," he added, in reference to his portrayal of former prime minster Tony Blair in 2006 film The Queen.