I believe the Boss BE5 was their first multi effects unit from 1988.
Then they came out with the BE5M next that was basically the same but you could program some patches.
Then the Boss ME10 came out around 93, fully programable, great sounds but harder to use, no knobs, menus and soft touch screen to adjust everything. My buddy got one new and used it for a while until he got a GT3.
He still has the ME10 but hasn't used it in years, I think he paid around $600 for it new!
Multi effects have come a long long way, I don't really like the more complex ones , I'd rather have a set of pedals, easier to use live, but the old BE5 is really like a small pedal board all in one.
Ibanez made some comparable units too that sound really good.