I've been tinkering on and off with hacks of the one-page game Tunnel Goons for a good while now, as well as with procedural dungeon generation, and have now arrived at something I'll be keeping largely as it is. That something is Sargolis, an adventure RPG using only a couple or three six-sided dice, with systems for both dungeon exploration and time spent in the ruined city above the 'campaign dungeon'.
You can grab that, Pay What You Want, here.
In addition to this, I'm also currently in the midst of converting some of my things into actual physical books – Fundamentals, Sargolis, [Infected] and Schema will all hopefully have arrived at or be nearing availability by the start of next year. However, these won't be POD books via Drivethru (or any other provider); these will actually be small print-runs of perfect-bound books made in my own home workshop. If you're interested in getting notified when and as these become available (that is, put on my personal mailing list for that project), email me at levi.kornelsen@gmail.com, just to say "Put me on the list for books" or something similar.