Should be a fairly Harry event as it is, what with the French'n'Saunders spoof "Harry Potter and the Secret Chamber Pot of Azerbaijan" set to press all the ericklendl buttons, a chance to win a Potter-esque car and so forth. I still don't even own the schoolbooks yet and may change that tomorrow.
Now the other interesting but unrelated thing that's happening tomorrow is the surprisingly well-organised Circle Line Party II, location to be revealed tomorrow morning. I had not realised the mad genius behind the coincidence. Now obviously there's not going to be any formal links between the two, for one is far too guerilla for the other, but the nation as a whole will be far more attuned to shenanigans and miscellaneous merriment than on any other day of the year and so be more likely to join in.
(Edit: third weird thing happening tomorrow is production of a web site from start to finish in four hours for Comic Relief. Go along to the BBCi studio in Aldwych and watch 30 of them blow fifty million quid of venture capital in four hours, or something - or just follow the web site as they produce it.)
Tomorrow, I really wish I was in London. If you are in London, take advantage of this. If you happen to be in London despite habitually living elsewhere then take advantage of this. If you happen to be able to contact some people who are in London at the moment despite generally living in Boston then tell them this now so that they can take advantage of it tomorrow. Hint, hint. ;-)