I fully understand why Wikipedia is blacked out today, and it is effective, serving to show just how much we (or I) have come to take it for granted.  I googled something and of course up popped the wiki answer... and the black screen.  Then I got cunning - I used the 'cache' option and, lo, I could see the page I wanted from Google's latest cache.  Probably not quite in the right spirit, but it helped me find what I was looking for.

I guess today students everywhere are having to do their own research... unless they, too, use the 'cache' facility in their search engine?

As one who contributes small sums to the upkeep opf Wikipedia, I shall be glad when it's properly back  - and hope they don't blacklist me for beating the blackout!