Cute solutions and something else...

AFAIK creating DOM elements with the help of Javascript is a very popular task. And there exist two popular common methods to do it: to use parentNode.innerHTML property or methods document.createElement() + parentNode.appendChild(node). Surely there are other methods like table.insertRow() or select.options[index] = new Option() but these ones are commonly used. Let's analyze them according to the following characteristics: compliance, speed, memory usage. See the sample page here. It demonstrates how to insert 1000 equal images about 1Kb size in the DIV via innerHTML or createElement.

1. Compliance

DOM:element.innerHTML

As there is no public specification for this property, implementations differ widely. For example, when text is entered into a text input, IE changes the value attribute of the input's innerHTML property but Gecko browsers do not.

It should never be used to write parts of a table—W3C DOM methods are to be used for that—though it can be used to write an entire table or the content of a cell.

createElement: +1

2. Speed

Firfox 1.5.0.4

• innerHTML — 1524, 1472, 1483
• createElement — 4687, 2584, 2573 (strange speed-up after page refresh)

Internet Explorer 6.0 (woah! really rocket-like speed)

• innerHTML — 360, 320, 211
• createElement — 360, 421, 390
  

Usually innerHTML is much more quicker than createElement in Firefox and a bit quicker in Inernet Explorer

innerHTML: +1

3. Memory usage

See these two memory diagrams below (private bites of Internet Explorer process):

So... Internet Explorer uses more memory when you try to insert HTML with images via innerHTML instead of createElement. Don't forget it!
Firefox doesn't have similar memory problems.

createElement: +1

The final score - 2:1 in favor of createElement

In most cases createElement is a more powerful method. And using something like
domEl() is more useful and quite simple.