I did it with d3.js and topojson, then I used the resulting svg image on the website. You can find the code here https://github.com/riccardoscalco/textures/blob/gh-pages/map...

In my opinion the "right" way for static things. Keeps the browser from computing, no need for the original data and libs. Of course being able to inspec other people's d3 code is fun on the other hand.

Thanks for the update! I was unaware of the power of geoJSON (also githubs neat mapping of them) and access to data from places such as gadm.org. Is that where you source the data?