FS: GuruROM for A2091/A590*

[mousehouse]

I've got an old rev 4.0 A2091 card sat on a shelf with a v6.1 ROM marked "1990".  What will this Guru ROM allow me to do?

The GURU ROM does a whole bunch of fancy stuff, some of which is detailed on Ralph Babel's page at : http://babel.de/amiga.html