I have often used a chippies type suede tool roll which fits in a waterbottle with the top cut off. This I fill with tools, pop in a sandwich bag and ride off with, usually on a bikes first outing to tighten up what beds in. Also teng tools mini rosso 1/4" drive set with screw alen torx bits and 5mm - 13mm sockets fits in a camel back, then put a 1/2 an old car sponge in there to prevent chaffing and use a 1/2 back bladder (before any one states the obvious this is expensive if you don't already have all these things)
Jez, I agree it is a cool idea BUT only if the tool quality is any good and to be honest these type of ideas often use tools made of case hardened butter to keep the costs down
Like the idea of high density foam in a water bottle to stoe stuff, make your own kit of good tools that you like, and remember, try different tools in different things, I have an awesome sykes pikavant screw driver that does almost all flat and cross head (including phillips) screws that you get on a bike and it also happens to do 3mm allen bolts up, Now thats a multi tool (doubles as a knife too in extremis!)
Somerset, like 'Heartbeat' with newer cars!
Retro MTB: 1992 Cannondale 3.0 Deore XT M730. 1992 Marin Pine Mountain Deore DX M650.
Retro road: 1992 Eddy Merckx Corsa Extra Telekom Shimano 600 STI. 1993 Dyna Tech Ti.
Modern: 2006 Wilier scandium Ultegra 6600. 2014 Wilier GTR Ultegra 6800.