In reply to yellow:
I do a lot of travelling so I tend to just move the same kit around from pack to pack. It's probably more than is needed for a day cragging but it saves having a whole other kit...
Plasters
Larger adhesive dressing
Antiseptic wipes
Compeed blister pads
Scissors
Small EMT shears (for cutting clothing, etc)
Tweezers
A small mirror (great for treating your feet)
A couple of pods of saline (for cleaning out wounds or eyes)
Ibuprofen
Ibuprofen & codeine
Antihistamines
Anti-diarrhea tablets
Indigestion tablets
Oral rehydration powder
I have a Swiss Army Knife in my pocket all the time anyway.
I think that's all of it. Like I say, overkill for cragging, but I've used every bit while travelling at one time or another.
SAVLON!