Another fantastic source of data and statistics.
The NationMaster database has just found its way onto my favourites list. The statistics page is the best I've seen for country to country comparisons in a variety of categories and draws its data from such sources as the CIA World Factbook, UN and OECD. Users can generate maps and graphs on all kinds of statistics with ease.
The data can be cross-cut in just about any way imaginable; per-capita, per unit GDP, imports, exports etc. The people behind this site have obviously put in considerable effort to produce a powerful tool. Another set of data that I enjoy is nuclear power capacity per person, or who has wrapped their arms around nuclear power the most. My guess would have been France... but alas, no. They've been just nosed out by the Swedes.