At work in the UK my flight bag is my headset bag. Enough room for my licence, spare specs., fuel tester, torch, some pencils/pens, a sick bag or two & spare PTT switch. Separate to that I have an A5 size aluminium clipboard.. .. .Don't need anything else since the a/c have their own charts etc.. .. .In Oz it was a bit different since generally you're expected to supply your own charts etc. My flight bag is an old yellow canvas satchel. It fits all the charts for Oz including approach plates plus the stuff mentioned earlier.. .. .Damn sight more convenient than those large pilot cases that seem to be the rage. I can sling it over my shoulder to carry it & it fits just in front of my seat when in use.