It is possible to use one central machine as a server to create your own"repo" (repository).
The benefits are that you can download the files once, and update multiple machines on the local network.
The disadvantages, though, are several:
- You need to install additional software of the server (PC used to cache the packages) and have it running during the update
- You need to download all packages (no easy way to cache just those on one of the PCs) which can consume quite a bit of space
- You need one repo per version of OS
I have 5 machines running various flavors of LL (from 1.0.6 on my PC to 2.4 on my son's), and I still update them individually directly from the internet. The update sizes are generally small enough that downloading them is not an issue. I have a linux server (Ubuntu 12.04) running quite a few services, but decided that caching packages was not worth the hassle.