The Research Discovery Engine I stumbled across this search engine when I was looking for some internet statistics. I'm not entirely sure what to make of it to be honest, because it looks quite interesting (and I certainly found it helpful), but the links to the 'About' and 'FAQ' pages are broken, and the last blog entry is quite some time ago. However, the facts themselves come from various reputable sources.
You can simply pop in your search term and see what it returns for you. The results that are returned give the fact, the source, when the fact was added and from where and when it was originally published, together with some keywords. Alternatively you can search by subject, such as broad categories like 'Internet' or more specifically, facts about something particular, such as students or Facebook. It's aimed very much at technology and consumer based information. Very irritatingly however, it doesn't link back to the original source, so it requires a secondary hunt on the facts website to find it.
So, a combination of really helpful and very irritating. But since I'm on a facts website, I can't leave without providing you with one, so here's your fact: "The iPad has over 90% of the tablet market in the UK (93.1%), Australia (93.2%), Ireland (90.2%), New Zealand (90.6%), Sweden (91.2%), Norway (92.7%), Denmark (95.0%), Iceland (93.6%), and Switzerland (91.7%)"