lazyness tricks

if you have lurked on haskell irc, you'd know that they don't have in very high esteem laziness in haskell, (they see it as a medium to guarantee purity)

but since in the end we need to play with the non-strict semantic. it would come handy to know some techniques only possible in a lazy language.

for example in http://obfuscatedcode.wordpress.com/2008/02/16/functional-pearl-trees/ the author shows how with laziness i can replace in all the leafs with the minimum value in one pass, instead of 2 that would require if we translate directly the strict algorithm to haskell

tl;dr laziness trick for haskell to make more efficient?

Just so you know, the inventors of Haskell consider the priority they put on making Haskell a lazy language a mistake