I echo the ratchet spanner comment above. Thought socket sets were fine, but the flat ratchet spanners are certainly a useful adjunct.
On the tools front the ones I really like, and hadn't previously been aware of are the facom L-shaped tubular spanners like these.
They don't seem to be anh benefit over normal spanners yet somehow they are just a little bit more handy for a lot of jobs
Also the eezee stitcher which is a sewing awl thingy for doing canvas and rucksacks and the like. Great piece of kit.
And lastly, the gas soldering iron. Just so much easier than a mains one and portable too. Especially handy is the hot knife fitting for cutting rope whilst melting the frayed ends. Much easier than using the gas ring and burnt fingers method