One of the great things about the MB02+ disc system is/was the DMA. Using the device's built-in Zilog DMA chip you could throw data around at very high rates, meaning some nice FX (such as
Multitech and other lovely graphics effects) were possible. Over on the
WOS forum Velesoft, the Czech hardware guru has mentioned the
Data-Gear, an internal mod that provides the same DMA functionality as the MB02+, without needing an actual MB02+. Nice, huh? In fact,
here's an example of what you can achieve - the green area is the time spent doing DMA. Yep, entire screen scrolling in about half a frame.
Of course the problem with mods like this is that they require people to have them in order for people to fully utilise the functionality (I know that's obvious, but why would you develop code that used DMA if only 7 people could run it?). Personally I'm a big fan of having a "vanilla" ZX for running software on, rarely using the bonus features of any addon device... but maybe that's just me.