I remember setting up battles in Operation Flashpoint mission editor, then placed myself as a civilian and observed the AI armies duking it out, despite some AI quirks it was lots of fun to edit or change the various units soldiers and vehicles positions to see how the battles would be influenced.
I had no idea you could do that, good to know. Not that I ever really looked into the editor.
My brother, having played a
lot of Operation Flashpoint, spend I'd say maybe %90 of his time messing with the editor and scenarios and modding. There is an enormous amount of cool stuff you can do with it. A favorite new sport we discovered was "place explosives under vehicle, run back, press boom, and see how high/far it will go." Or jacking up the max speed of a bicycle into insanity. And yes, giant gratuitous tank-on-tank battles.
I also heard some hilarious modding bugs, such as accidentally turning things into the default unit, which was a BMP, leading to BMPs within BMPs, and possibly BMPs inside infantry.
EDIT IN RE ACTUAL TOPIC: Little Wing Pinball games (the earlier ones are better for this), demo mode. You don't need to actually have the game. Just watch the random yet-perfectly-reflexed computer accidentally get more and more points, which in my case ends up with insane scores beyond my reach.
Also, if you can find it, Crush Deluxe (futuristic sports simulator) actually offers to show you computer-only games in your league. I guess it's like actual sports, then.