When was the last time you did any development without internet access though? For me at least, I've found it to be pretty much a necessity.
I think some form of VCS access to these services determines their ultimate usability.
[1] https://en.wikipedia.org/wiki/Bergen_Line#Line
Side-note, the Norwegian broadcasting service, NRK did a pretty crazy stunt filming the whole thing, and airing it on tv: http://nrkbeta.no/2009/12/18/bergensbanen-eng/
The only thing I am missing is a local pypi to cache my commonly used 3rd party apps.
I use my laptop a lot on the go. Trains, Airlines, Pubs, Coffeeshops, and so on. Some places will have Wifi, or others I'll be able to tether. But I don't like to rely on having it to be productive.
Have XAMPP running or some local server. Go have a blast.