I was inspired on my indie dev project 'Miniature Multiverse' by something completely unrelated to video games.
Inspiration for game elements can come from outside the field you're in (gaming) and often that helps. Recall Will Wright, taking an urban planning course in college and thinking, this (building and zoning and running a city) could be a game and that ended up being SimCity. Or how the notion of megahit 'The Sims' came from watching a child play with a dollhouse. Try taking something outside video gaming and imagine how it could become part of the design of a game.
Namely, in my case the idea for a current project emerged from model railroading and the way people create those super detailed miniature scenes! In 2010 I looked at some first person camera run throughs of larger scale model rail sets and thought, wouldn't it be interesting to make a wide range of imaginative fantasy worlds (like a Myst game, etc) but made with detailed, physically real materials, and allow players to explore them in first person view?
http://www.MiniatureMultiverse.com
The miniature idea also crossed my mind in other permutations, like a racing game using remote control of RC cars over the web, in a realistic scale model racetrack. You would mount cameras like GoPros inside them and stream that video to the players plus overlays for vehicle control. I still have yet to attempt to figure out a way to do this as code is one of my weaker spots.
Another example of this was my project Vivid Minigolf. It was jokingly referred to during early development as 'Miniature Miniature Golf'. I made the error of building it in Gamesalad initially but now am redoing it in a much improved form, with Construct 2. That will avoid the arbitrary filesize limits on HTML5 and other platform output games that GS imposed.
I recall having discussions of my ideas relating to accelerometer-based AR (augmented reality) in 2011 or so, and when Pokemon GO showed up and others were saying how cool the concept was, I just shrugged and said 'why did this take so long?' and 'why haven't they pushed it further than this by now?'
I love the idea of an AR / VR hybrid escape room, in which the player's Vr headset was a window into an alternate form of the physical room. Think about it this way, there would be a very minimalist physical space to explore, just rooms with plaster walls and roughly sculpted shapes, and the app loaded when entering the room would be in the headset mounted onto player's head, converting the boundaries of the physical space into a much more interesting and imaginative virtual world, such that the virtual space would be tracked continually to match the layout and 3d position of the real space, creating a breathtaking virtual environment to physically explore that is also entirely tactile. I am now looking at the Aryzon headset as a possible way to someday test the idea. It would be an entirely other level of VR. Alternatively, laser tag + VR, the normal tag overlaid with an illusion of using 'actual' powerful weapons, in a scifi setting, otherwise same core concept though.
These are just a few ideas of mine.
I also have a bunch of stuff on itch, including a lot of stock media asset packs. If you want to see my ideas realized someday, buying these wouldn't hurt, and the asset packs are great value regardless especially during holidays (my next sales are Easter, Memorial Day, and July 4th, on those days bundle sales should be running that give indie game devs access to 70+ 3d assets, 120+ video elements and overlays, and 1400+ texture image files and decals, for about a dollar!
You may also want to look at some of the links there. http://www.TriumphantArtists.com is about to be updated heavily with new informative articles for creative types, and there are other venues like other domains I run, my social media feeds (Twitter, FB, Instagram, and Pinterest), and my Etsy shop that may be worth a look.
https://www.etsy.com/shop/MatthewLHornbostel
Thanks for reading.