"Beer bike" - good idea. You must know that Berlin is a city of bicycle kleptomaniacs. Stealing bikes is considered a sport there. It´s a good idea to have an old bike so you don´t have to worry about it while you waste yourself. The police don´t care about drunk cycling, at least they never bothered me when I lived there. They stopped me several times, but only because the rear light didn´t work. They must have noticed I was pissed, but that was never an issue.
The "bed and bike" thing is a good idea. There are very popular bike routes in Europe, for example the one along the river Danube. We always have tons of cyclists staying here during summer.