commented on Styromaniac
Closest you can get probably. I do agree though, being able to download game / updates / cache it for sharing on LAN wherever you go would be awesome.
I can get fast internet in town, but in rural areas I get max 1M down on the best of days. It's usually more like less than 300K down.
The same reason I use apt-cacher-ng for my Ubuntu system. I cache all the packages so I can update more than one system, or if I nuke mine, I can update to current from a release point.