Where do I begin? :-)
I've got the following:
A1200 in Power Tower with BPPC 603e+ 060/210Mhz, 3.1 roms, 128MB Fast ram, Grex1200 PCI, Voodoo 3, Ethernet, Sound.
A1200 in D-Box 1200 Tower with BPPC 603e+ 060/240Mhz, 3.1 roms, 192MB Fast ram, MediatorSX 1200 PCI, Voodoo 3, Ethernet, Sound, Spider2 USB.
A4000D with CSPPC 060/233Mhz, 3.1 roms, 128MB Fast ram, Buster 11, Grex4000G, Voodoo 3, Ethernet, Sound, Spider2 USB.
Amiga 3000D with A3640 rev 3.2, 3.1 roms, 16MB Fast ram, Buster 11, DMAC 4, Ramsey 7, WD SCSI 8
Amiga 2000 with Blizzard 2060, 3.1 rom, 128MB Fast ram, Picasso IV, Delfina ZII light, Ariadne Ethernet
Amiga 500+ with Ematrix 530, 128MB Fast ram, 3.1 rom, internal 2.5 30 GB Hard drive.
Only one system gets used regularly, but it was sure fun to tinker around with assembling all of them and stuff.
I also have expansions all over the place which could probably almost duplicate my existing upgraded collection, that is if I bought a stock A500, A2000, A1200, A3000, and A4000D. :-D