An article about someone telling his experience of slowly growing a business (targeted at school teacher if I remember correctly) year after year eventually led to a sizeable lifestyle business.
re: all the zip suggestions. Apple already provides a solution:
"Internet-Enabling a Disk Image
Although all disk images can be transported through the Internet, users need to open them, retrieve their contents, and discard them. An Internet-enabled disk image automates this workflow. After a user downloads an Internet-enabled disk image from a network using a web browser, the image is automatically opened, its contents placed at the user’s download location, and discarded (in the Trash). This improves the manual install experience by performing a few tedious tasks for the user.
"
Too few devs seems to be aware of this.
Anyway a custom installer for Firefox is a backward idea.