Mike Dickison’s blog Pictures of Numbers is fab. It’s all about clear, simple, effective data visualisation for scientists. Three posts that I thought were particularly useful were:
Better Axes: improving readability, increasing the information content and decreasing the clutter in your graphs.
Fixing Excel’s Charts: Surgery for the annoying defaults that Excel has, and how you can actually get an effective and high-impact piece of data presentation out of the poor maligned piece of microsoftery. [I spent a fair bit of time mucking about with building custom templates for graphs while I was writing my thesis, and they're really worth the time investment.]
Maps for Scientists: Two posts, one about choosing maps and one about using them. Both sensible and aimed at presenting and highlighting the right types of geographical information.
My colleagues are probably bored to tears when I bang on about design and science, so it is great to see a kindred scientist out there.