Following on from men working on their own for little or no reward I nominate Alfred Wainwright.
He was a shy, modest man who was born in Blackburn but fell in love with the Lake District the first time he went there.
He eventually got a job with the council in the Lake District, in Kendal.
Even though he was in full time work he then set about producing a series of guides of the Lake District which are works of art in themselves.
The books took him 13 years to produce.
Each weekend he would set out by bus (he had no car) and walk up and down different fells all weekend.
In the evenings he would HAND DRAW every single word and picture in these books, giving an overview of each fell, the different ways up and down, the views from the top and so on.
He was a perfectoinist and if a mistake was made on a page he would screw it up and start again.
He was so determined to make the pages look neat that he lined up the text in both the left margin AND right margin, not easy with hand written text.
The 7 books were published between 1955 and 1966 and are STILL used on the fells today. Before seting out on a lake district walk people still say "got your Wainwright?"
Go into any decent bookshop and they will have copies of Wainwright in the travel section.
After producing these 7 books he then produced other books of walks in Scotland and so on, as well a books of his drawings etc.
More on his books here:
http://en.wikipedia.org/wiki/Pictorial_Guide_t o_the_Lakeland_Fells
There is also a Wainwright society
http://www.wainwright.org.uk/