I use a pencil case to hold my short acting insulin pen, plus a spare cartridge of short acting and one of long acting at all times - that means I always have at least a week's worth of insulin with me when away from home. One bloood glucose testing kit is in same rucksack or jacket pocket as insulin in use. If I'm planning to be away, I carry a bum bag, which contains long acting pen, test kit, small medicine bottle or 35mm film pot for used sharps, with a spare cartridge of long acting and one of short acting, plus my glasses / contact lens kit. That means I'm set for 2 weeks.
Packets of jelly sweets are spread among various pockets in jacket / trousers / shorts / rucksack. Personally, I regard trying new foods of all types, including sweets, one of the pleasures of travel, so I often find packets with labels in German / Icelandic / Spanish / whatever the last place I visited, which brings back happy memories.
If I am planning to be away for longer, then I carry spare insulin, in case one pack is lost. I prefer a small stainless steel vaccuum flask, which usually has cool water from fridge, except when on plane, as it doesn't leak nor need to be exposed to air like Frio in order to keep insulin cool, plus it offers better protection against vibration, dropping etc, plus I already had a couple when diagnosed nearly 19 years ago, and I haven't had to replace them.
I haven't bought a rucksack since a framed one I needed for carrying heavy work documents about 8 years ago. For fun events, I rely on kit I'm given for volunteering on various mountain races. Currently relying on a lightweight running backpack from Dragons Back Race in Sept 2012, and expect to get another at Dragons Back June 2015.