Ripdev have just released a free update to our package installer tool, InstallerApp, for both Mac OS X and Microsoft Windows. Among other things, we have ensured it works on Mac OS X 10.6 Snow Leopard, removed support for Installer repositories (that are no longer supported anyway), and stripped off the Pusher technology in favor of the existing jailbreak solutions such as PwnageTool and redsn0w. To install stuff onto the iPhone, simply install package named InstallerApp Support from Cydia or Icy on the device (from our repository apt.ripdev.com) and there you go!
As a result, InstallerApp is now 1.2 Mb (or 4.2 for Microsoft Windows) as opposed to 17 Mb before.
Enjoy.