Our company makes wyBuild: http://wyday.com/wybuild/ . It comes in 3 parts (wyBuild, wyUpdate, and the AutomaticUpdater control). wyBuild makes the tiny update patches, wyUpdate is the open source updater (BSD licensed) and the AutomaticUpdater control is the open source control that adds the ability for fully automatic updates (LGPL Licensed).
Here are the links to the source code, for those interested:
It might be that you came up with this icon independently but anyway it's better to change it.
Terrific product otherwise. I'll try to convince people at our company to tale a look at it. We currently have our own AutoUpdate implementation but it downloads the whole .msi files.
I like that Sparkle's open source, and it's being used by many open source apps on Mac already. Getting the auto-update software to actually be secure is not trivial either (a recent attack was discovered on Acrobat's updater for example).
> I am not aware of a win or a Linux (I mostly work on Linux) solution either.
I'm trying to say this without sounding snarky, but why the heck would you need this on an operating system that already gives you apt-get, pacman, yum, portmaster, or what have you?
Also the WiX people have been working on something along these lines, but I don't know how mature that project is or if it's even still a project any more.
EDIT: Looks like Google's made a separate open-source project of its update framework, Omaha, which is apparently how Chrome gets its updates. So I guess you can get Chrome-style auto updates in your own applications now. Don't know if Google's nifty binary diff compression algorithm is included.
At the moment the biggest problem I see is that there is not a framework for doing this, it has to be build from the scratch every time