In my acoustic guitar case:

Guitar
Spare strings
Tuner
Small snips
Tuning peg roller/peg extractor gizmo

Picks are carried in my pocket.

If plugged in and with amp, the large plastic box (with lid) contains:

Assorted 4-way plug boards
Kettle leads
Guitar jack cables
DI box
Floor pedal tuner
Mics
Gaffer tape
XLR cables
Male/female XLR adaptors