2 basses in VERY hard cases. 1 fretted 1 fretless (both fivers)
tuner, pre and power amps in a 6 slot rack.
410 cab
212 cab
pedal board in carry case with all leads I need for the show.
another bag for stands, spare leads, spare strings, spare valve, toolkit, gaff tape, towel etc.
To the original poster, i think it's vital to carry enough to cover every eventuallity. We don't play multi-band gigs that often so borrowing kit isn't usually an optio.