Running debian stable, I know I can use unattended-upgrades to automatically download and install upgrades.
However, running debian unstable, I would be extremely reluctant to automatically install upgrades due to the nature of the distribution being unstable. However, I see nothing wrong with pre-downloading the upgrades for convenience. Is there any way to download all the upgrades that I might want to install so that when I aptitude upgrade I don't have to sit and wait for everything to download?
You can assume that disk space and bandwidth per month aren't an issue. (In fact I have considered simply running a full mirror and using my local mirror in my sources.list, but I feel this might be going a tad overboard.)