Luggage Pods

Apologies if this has already been covered but could not find it.

On a (cold!) flight back home from hols I was wondering about luggage pods carried on fighters.

1) Are these big enough to carry every the pilot (or two pilots) need?
2) Whats stops the actual luggage from freezing in flight?
3) Other then pilots luggage do they have other applications?
4) Anyone got any decent pix of them?

Thanks in advance.

Rim