These three tools (drush make, Aegir and Dropbox) have come together to produce a release system that means I don't have to ssh into a remote server to deploy a new version of site. This means that I can do releases really, really simply, and actually with nothing more than a web browser1. Let me explain:
If you aren't using Drush make, then you should look into it. Essentially you specify a manifest of all the code that makes up you project and then you can ask drush make to assemble the code for you. It has some really nice features, like being able to apply patches and checkout code from CVS, git, etc.
Its real power comes from the ability to recursively make projects. If one of the projects contains a make file, then drush make will parse that and use that manifest of code additionally. The main use for this is to pop a make file in your install profile, and then use that to specify all the projects and patches that your profile will need. You can then have a 'stub' make file whose only job is to download Drupal core, and your profile. For example, the stub install profile for this very site looks like this:
core = 7.x
api = 2
projects = drupal
projects[computerminds][type] = profile
projects[computerminds][download][type] = git
projects[computerminds][download][url] = email@example.com:computerminds/computerminds_website.git
projects[computerminds][download][tag] = release-2.3
Line 4 just tells drush make to download Drupal, and then the rest are to get the install profile, which happens to live on github in a git repo (a private github repo mind you.)
From there drush make finds the make file in the profile, and parses that and goes on to download all the code needed for the entire site.
Aegir and make files
I'm not sure when the feature was introduced, but Aegir can use make files create new platforms for sites. Point Aegir at a local copy of a make file and it'll go away and run drush make for you and add the platform to Aegir. This is great! If you can get the stub make file (remember that was the simple one above) onto the server running Aegir, then you can provision a platform with your profile available easily. However, there is still the step of getting the make file onto the server...
Dropbox is the rising star of the file sharing world. It makes syncing files between computers painfully simple. So why not onto a server too?
Following the instructions to install Dropbox headless you can get set up with Dropbox really simply and start automatically syncing files to your Aegir server. So pop your stub make file in your Dropbox and it'll get synced over to your Aegir server in no time, you can then provision a platform in the Aegir frontend!
Putting it all together
So, practically how do we use this? Well, suppose that we want to work on a new feature of this very site. We would work busily away in git, committing, branching, merging, adding new projects or patches to the profile's make file, all the fun stuff, then when we're good to go, we'd make a tag in the git repo. Then we just open up our stub make file in Dropbox, and change the release tag to our new tag. Give Dropbox a few moments to sync, which is likely less than the time it takes to log into our Aegir instance. Move over to Aegir, provision the new platform based on the make file, and then migrate the site over to use the new code. All lovely, and not a ssh login in sight 2.
I'm still not entirely convinced of the workflow using drush make, it seems that you have to rebuild your code base entirely quite frequently, which is quite a waste of time and bandwidth. There is an issue on drupal.org to enable rebuilding of makes though that seems to have stalled. It's also quite a big shift in how you work, and you don't always have everything in a version control system, so you can't make random hacks to everything and then just revert them. So, there are some wrinkles that need to be worked out, but it's the future I tell you!
It's likely that one would still want to other tools, like a local development environment or a local filesystem, but you don't technically need these things for this process. ↩
Technically we could do our git work using the github web interface, and edit the Dropbox file using theirs, otherwise, yes, we'd probably be using ssh for git operations. Not for logging into production machines though! ↩