Daniel Krook has good news in list form for the IBM OS users out there (in list form) - the different systems that have PHP ported over:

The little language that could has made its way to z/OS. It's an older PHP 5 release, but PHP 5 nonetheless.

The list is of the four System * series:

• System x: check.
• System i: check.
• System p: check, check.
• System z: check.