Very strange day for me so far. A couple of unusually huge clicks early this morning (£15/£5) then things got very slow for the rest of the daylight hours, with much lower CPC and CTR across all my sites. Things seem to be picking up a now, however, and I'm well ahead of where I would normally be at this time of day, so can't really complain. Never had an adsense day quite like it. It all evens out in the long run, I find, but sometimes its just so bizarre.