I can't think of a game which uses that sort of technique, but various demos do, including the 25th Anniversary demo from 2006. The scrolling text says there is an extra bit I haven't found. Wonder if it find it before the 25th anniversary of the 25th anniversary? www.youtube.com/watch?v=2LOZ...
Tip - hold SPACE down when you're using it to skip a part...
Oh, that video is not quite right. There section at 2 minutes that has a black square bouncing around, it's meant to be a ball that says ZX81, so whatever that was running on doesn't support all the hi-res modes used. I use this as a test program, so I am used to spotting when bits don't work.
The video shows the demo twice. Apparently, the first time w/o HRG, the second time with HRG, logos and all. (At least, I think this is about HRG, since, what do I know abut UK doors and their favourite stoppers?)