JavaScript

• MediaWiki/js
• User Scripts ala Grease Monkey or Userscripts.org

Dan Phiffer wrote this little greasemonkey script that turns any mediawiki article into a slide presentation

// ==UserScript==
// @name           Wikipedia Presentation
// @namespace      http://phiffer.org/
// @description    Turn a Wikipedia article into a presentation
// ==/UserScript==

var wikipedia_presentation = {
setup: function() {

this.sections = [];
this.pos = 0;

var body = document.getElementsByTagName('body')[0];
this.orig_markup = body.innerHTML;
var markup = body.innerHTML;
var start = 0;
var end = markup.indexOf('<span class="editsection"');
while (end != -1) {
start = markup.indexOf('</span>', end);
end = markup.indexOf('<span class="editsection"', start);
if (end == -1) {
end = markup.indexOf('<div class="printfooter">', start);
this.sections.push(markup.substr(start, end - start));
end = -1;
}
this.sections.push(markup.substr(start, end - start));
}
if (this.sections.length > 0) {
var div = document.getElementById('bodyContent');
var link = div.insertBefore(document.createElement('a'), div.firstChild);
link.innerHTML = 'Start presentation';
link.setAttribute('href', '#presentation');
link.addEventListener('click', this.start, false);
}
},

start: function() {
var body = document.getElementsByTagName('body')[0];
body.innerHTML = '';
body.style.textAlign = 'center';

var prev = body.appendChild(document.createElement('a'));
prev.innerHTML = '&larr; Prev';
prev.setAttribute('href', '#prev');
prev.style.font = '11px verdana, sans-serif';
prev.addEventListener('click', function() {
wikipedia_presentation.prev();
}, false);

body.appendChild(document.createTextNode(' / '));

var stop = body.appendChild(document.createElement('a'));
stop.innerHTML = 'Exit';
stop.setAttribute('href', '#exit');
stop.style.font = '11px verdana, sans-serif';
stop.addEventListener('click', function() {
wikipedia_presentation.stop();
}, false);

body.appendChild(document.createTextNode(' / '));

var next = body.appendChild(document.createElement('a'));
next.innerHTML = 'Next &rarr;';
next.setAttribute('href', '#next');
next.style.font = '11px verdana, sans-serif';
next.addEventListener('click', function() {
wikipedia_presentation.next();
}, false);

var slide = body.appendChild(document.createElement('div'));
slide.setAttribute('id', 'wikipedia_presentation');
slide.style.width = '780px';
slide.style.margin = '10px 10px 10px 20px';
slide.style.textAlign = 'left';
slide.style.font = '2em verdana, sans-serif';

slide.innerHTML = wikipedia_presentation.sections[0];
var items = slide.getElementsByTagName('li');
for (var i = 1; i < items.length; i++) {
items[i].style.display = 'none';
}

document.addEventListener('keypress', wikipedia_presentation.keypress, false);
},

stop: function() {
var body = document.getElementsByTagName('body')[0];
body.innerHTML = wikipedia_presentation.orig_markup;
body.style.textAlign = 'left';
wikipedia_presentation.setup();
document.removeEventListener('keypress', wikipedia_presentation.keypress, false);
},

keypress: function(event) {
if (event.keyCode == 39) {
wikipedia_presentation.next();
} else if (event.keyCode == 37) {
wikipedia_presentation.prev();
}
},

prev: function() {
this.pos--;
if (this.pos == -1) {
this.pos = this.sections.length - 1;
}
var slide = document.getElementById('wikipedia_presentation');
slide.innerHTML = wikipedia_presentation.sections[this.pos];
},

next: function() {

var slide = document.getElementById('wikipedia_presentation');
var items = slide.getElementsByTagName('li');

var hidden = 0;
for (var i = 0; i < items.length; i++) {
if (items[i].style.display == 'none') {
hidden++;
}
}

if (hidden > 0) {
items[items.length - hidden].style.display = 'list-item';
return;
}

this.pos++;
if (this.pos == this.sections.length) {
this.pos = 0;
}
slide.innerHTML = wikipedia_presentation.sections[this.pos];
var items = slide.getElementsByTagName('li');
for (var i = 1; i < items.length; i++) {
items[i].style.display = 'none';
}

}
};

wikipedia_presentation.setup();