Today I went to a coffee shop and ended up making this music draft on the iPad while drinking coffee (I used GarageBand). It is pretty cool what you can do with this thing in a short period of time (though I still have a hard time playing its virtual keyboard). In case anybody is interested: the downside is that the audio or midi tracks cannot be exported to a PC to correct errors or to add other stuff. It can only be exported to a Mac computer with GarageBand on it, so that is a bummer. The GarageBand for iPad has rudimentary (as far as I know) mixing capabilities, so you cannot get too fancy when mixing down a track (I did not even use those options actually). The only “real” instrument for this track is the guitar, which I recorded once I was back home (I used the internal mic on the iPad). For the drums I used one of those loops that come with the software.
At the coffee shop I ended up buying a book on 18th and 19th century European architecture. It has a couple of pages devoted to the almost Sci Fi French architect Étienne-Louis Boullée. This is his famous (and needless to say never built) drawing for his Newton cenotaph (he thought of this in 1784!):