Let's look at the beginning of may: Linux Audio Conference in Utrecht, for sound junkies of all shapes. Phonon? Nope. But Reinhold Kainhofer -- once of KPilot and KDE PIM -- is speaking on music notation standards. I should drop by -- I still owe him 20 EUR for domain registrations. Lots of other things that make me think "gosh, people do that on computers too?"
Right after the LAC you could move to Ede (about 24 minutes by train) for the NLUUG Spring Conference on System Administration with the LHC on tap. Yes, it needs system administration as well if it's ever going to blow up the world.
There's a gap then -- fill me in, folks -- and end of May will see the Ubuntu 10.04 release party on the 29th. That should keep everyone busy and I've got some Ubuntu Thinking Putty to inflict on various people there.