Working on a non-profit project and wondering if there's a standout wireframing tool for website design. I've taken photos of collaborative whiteboard drawings and now I want to put the results into something slightly more professional looking for review. For obvious reasons I'm not interested in anything that looks too much like the finished product or takes longer than it would for me to write the HTML.

I checked out jumpchart, but that only seems to let you do content panes, not draw whole page layouts.

Free or close to free is desirable - for instance jumpchart licensing seems very reasonable.