I love anything with potatoes - shepherd's pie, bangers and mash, french fries, rosti ... Apparently, the UN has declared 2008 as the International Year of the Potatoe and is hoping that its merits would help alleviate poverty and promote economic development.
The spud was first domesticated in the Andes (there are 3,500 edible varieties!) and carried to Europe in the 16th century. Its value lies in its high yield and almost perfect balance of nutrients. Potatoes can produce more energy per unit area per day than any other crop and it's possible to subsist on a diet of spuds with very little else.
Apparently, it underpinned the industrial revolution in England in the 19th century by being a cheap source of calories and an easy crop to cultivate so it liberated workers from the land. But there was also a downside with the Irish potatoe famine of 1845 when 1 million Irish perished because of the potatoe blight.
There's a book out (if you want more details on this tuber food) - Propitious Esculent (Helpful Food): The Potatoe in World History by John Reader - on the biography of the spud; the world's 4th largest food crop (after maize, wheat and rice).
Maybe we should all start growing and eating more potatoes, considering the fast rising prices of wheat and rice (this blurb was inspired by spud articles in The Economist March 1st '08).