Are there any cordless power tool systems that offer a corded option?
Believe it or not, they do make such things.  For example the Greenlee AC Adaptor for 18V Cordless Tools. 

I have not heard of a "system" like that though.  I suspect that's related to the fact that I've never met a pro who used or even wanted one.  When battery-powered tools finally became usable, we all pledged our firstborns to whatever god made that possible and we never looked back.  

Cameras, laptops, etc. can all stay in one spot for extended periods as they do their job.  Power tools (at least the kind that come in cordless varieties) are in constant motion.  Dealing with cords and sockets is a major time, safety, and infrastructure disadvantage.

If your tool stays in one spot enough to where you ponder an AC backup, you're often better off just buying an AC-powered tool for that job.  It will: be cheaper, have more power, and be more energy efficient than jacking AC to the cordless tool.

But, if you're really jonesing to do the 60 hertz shuffle ;) and you have some electronics skills, you can rig up your own AC system, a little like this guy did -- Except I would use a proper-sized DC supply and wire it to an old battery pack (¡with the battery cells removed!) instead of hard-wiring it to the tool.