Been catching up on your gravity shooter reviews, and I assure you this wasn't intended, but I still find it funny that we both reviewed mouse controlled arcade style games around the same time and then went on to review Asteroid descendants at around the same time as well. I was actually unfamiliar with Gravitar until your review, and then it ended up coming up when I was looking up Asteroids history too!
Also, the link to play Thrust gives me a 403 forbidden error. Is this a region lock or IP issue? The entire BBC Micro site seems inaccessible to me, so I might just be unlucky.
Also was meaning to ask if you're familiar with Pixeljunk Shooter? I remember playing it back on PS3 and I recall it shared a lot of elements with the gravity shooter genre (physics, tractor beam, etc)