AmiKit contains Matrix screensaver called "glmatrix_68k.exe". However it was disabled since AmiKit 1.2.0.
To enable it again click the taskabar -> Tools -> System -> WBStartup+Prefs and enable "glmatrix_68k.exe" entry.
Or simply move it from AmiKit:WBStartup/Disabled to AmiKit:WBStartup folder.
Next time you start your AmiKit the screensaver will be active. The default timout is 900 seconds but you can modify it through the Exchange tool. Run Exchange, select "GLMatrix" entry and click "Show Interface".
Don't forget to install AmiKit12x-fix.exe as it contains important file for the proper functionality of this screensaver (because it uses QuarkTex).