As far as repairs are concerned? I guess it could be used to check X & Y outputs of a vector board, right? Anything else it could be good for? Just wondering if it's worth keeping around...
It looks like it does XY, so it'd probably be decent as a test XY monitor. From a quick search, I believe a 5MHz scope, so it'd be okay for troubleshooting simple stuff too, though a little clunky.
It's useful. It's better than a logic probe for debugging boards - you can actually see what's going on. If it does have an XY mode you can use it as a test monitor for vector stuff. Plus, it's always fun to hook a CD player into it and watch the waveforms.