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I'm doing javascript on a daily basis at the moment. I'm coming from an OO background and most of the code I have contact with is somewhat procedural/OO style. I'm looking for good examples that solves more or less typical web programming tasks but in a functional manner.

I'm not interested to have any arbitrary example that just looks like functional. I'm looking for an example that can show how to use the functional powers to solve problems better than with another approach. I know this is kind of subjective/style dependent but don't make it too hard for yourself (myself).

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Firstly, you want to comprehend what functional programming means; that is, what are the core concepts and how well the language allows you to adhere to those concepts. For OOP, the core concepts are encapsulation, inheritance, and polymorphism (or just message passing for smalltalkers). For FP the central tenet is referential transparency (which implies statelessness). Trying to program in a functional style in a language that doesn't support functional features (e.g. functions as first class objects) will be awkward if not impossible. Same with programming in OOP in languages that don't have OOP features.

Fortunately Javascript is multi-paradigm and supports both. Instead of looking for examples of code that is 'functional' just think about all the ways in which you can ensure referential transparency and this will naturally lead to using the FP features of the language such as lambdas, closures, higher-order functions (e.g. map, reduce, filter), currying, etc.

Seriously, this is not meant to be a non-answer. I really think this is the most motivating and efficient way of approaching it.

That said, here are some hopefully helpful links.

  1. FP programming in JavaScript

  2. Mostly adequate guide to FP

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I find the answer quite ok. I wasn't really sure while writing this question. My assumption was javascript would be considered as a functional language but now I see it is not really. And if I think about it it isn't even a real prototype language :)
Probably more fair to say that JS is not a 'bondage and discipline' language (although that usually refers to the type-discipline). It easily permits almost any style of programming. 'Functional' and 'OOP' are just styles. Some languages force you into one style (Java and OOP), some strongly encourage one style while permitting others (C# with OOP and Functional) and some really don't care, like JavaScript.
I've been meaning to learn more about the Functional use of JavaScript, this is a fantastic answer. Also, to add to what @Kevin Hakanson has posted below, here's a youtube video featuring Douglas Crockford
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Douglas Crockford links to Functional JavaScript from his JavaScript resource page. Here is a snippet from the site:

Functional is a library for functional programming in JavaScript. It defines the standard higher-order functions such as map, reduce (aka foldl), and select (aka filter). It also defines functions such as curry, rcurry, and partial for partial function application; and compose, guard, and until for function-level programming. And all these functions accept strings, such as 'x -> x+1', 'x+1', or '+1' as synonyms for the more verbose function(x) {return x+1}.

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One example that I remember is a function that is bound to an object for registering as event handler

function bind(aHandler, aBind) { var handler = aHandler; var bind = aBind; return function(event) { return handler.call(bind, event); } }

It is dealing with scopes (currying) and is handy.

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How do you call this bind() function?
Say you have an object myObject that has a function someFunction. Then you call element.addEventHandler("eventtype", bind(someFunction, myObject)). So on event time the function on your object is called
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Have a look at jQuery. This blog makes a good case that it's in a functional style. http://importantshock.wordpress.com/2009/01/18/jquery-is-a-monad/

That said, JS isn't really a functional language (IMO), so trying to force it to be one is probably not the most efficient path as a developer (using a screwdriver as a hammer -- still gets the nail in the wall but not quite as fast :). Then again, it is a lambda language.

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Can you elaborate on this, please? What are your main reasons to state javascript is not a functional language? What is different/missing?
I should have been more clear. It's not a "purely" functional language. Certainly you can leverage lambda and closures to write in that style, but I think the resulting syntax is similar to what happens when we try to force JavaScript to do classical inheritance. It just looks a little strained. Full disclosure: I don't code in the functional style, so for you folks who do, the syntax is probably perfectly acceptible.

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