Tricky to find the most cross-browser-compatible solution (IE6 included).
Three columns, the two on the sides are responsive and adjust with screen.
The middle column should be empty, but with a fixed width:

It’s easy to make them all responsive: http://jsfiddle.net/Baumr/sZehH/2/ (in this case, the middle one isn’t even a column but just a margin — which is nice).
<section>
<div>
<p>Column 1, lorem ipsum dolor bla bla dogs and cats</p>
</div>
<!-- Best if Column 2 is a margin or something -->
<div>
<p>Column 3, lorem blops dolor bla laa cats and dogs</p>
</div>
<section>
I’ve considered using position:, but it can get messy…
Any ideas? Thanks in advance.
What about using an inner element for spacing? Could be another DIV tag inside each column:
http://jsfiddle.net/sZehH/3/
HTML:
CSS:
I’ve used the paragraphs that where already there, but you probably will have more than one element, so you will have to add a wrapping element to account for that.