Of foldable bikes
But lacking of parking place the obvious choice was to get the bike back home with me. You just cannot park it in the streets if you want to keep it for a long time. The problem was, then, to get the bike from the street to my flat.
I've seen some people tilting bikes front-wheel upwards so they can fit it in the elevator but it didn't seem to me very convenient, and then you'll need some real estate inside your home anyway.
I've learned about several brands making foldable bikes (Dahon, R-M, Brompton). Minutes later I've learned too that this stuff was expensive. I finally settled with a Dahon's Vitesse 3D for 425 Euros. It was a trade-off (and one of the less expensive alternatives) between folded volume, price and comfortable ride. I'm quite happy about the bike although I still think it could be cheaper (you can get a better price in USA).
Now I'm getting a second bike for my kid to go to school, but a 16" Dahon's Piccolo seems to be not as foldable as my 20" Vitesse. It can be folded quite compact but using tools and not the 15 seconds it takes to fold the Vitesse.
By the way, forget my complain about G4U software. It had worked Ok, but somehow our system's operation fill all the data partition until the system crashed.