Using the stairs instead of the escalator

I was pleased yesterday to discover the stairs at the new John Lewis in Cambridge (had them all to myself and was not blocked by those bizarre shoppers who have so much time to waste that they can afford to use it by drifting up and down escalators instead of walking). However, the shop completely fails to put the floor numbers or any store guides on the stairs, so you've no idea where you are or what you'll find there.
Why don't we all go up and down the stairs? I'm certainly going to make a policy of it from now on.
I thought, while we're on this theme, you would find this amusing.

Simple devices and inventions with negative commercial potential II: disposable gaiters for cyclists

The problem: bicycles with derailleur gear sets don't have proper chain guards. It's easy to get your summer trousers filthy, or your beautiful new pale coloured suede boots. A well-oiled chain and smart leg-wear don't mix easily.

The solution: Tear off the leg of an old worn out pair of pyjamas, the leg end of a worn out pair of knee-high socks, the sleeve of an old shirt or sweater, or just any piece of discarded cloth garment or sheet. Pull it on over the lower leg end of your trousers/boots, or, if it is not a tube, wrap it round the leg and tie the corners together on the outer side at top and bottom. If it's too loose, tie it up with a spare shoe lace or an elastic band.
When you get to your destination, slip your leg(s) out of the gaiter(s) and roll the gaiters up in your pocket or bag. The sleeves of a silk shirt are particularly small and light weight for this purpose.
Now you're instantly smart and presentable... When the party's over, you pull the things on again before riding home (make sure they're not inside out!).
When the gaiters get too dirty, throw them away and find a new pair.

Simple devices and inventions with negative commercial impact I: No-bracket bike lights.

As Christmas approaches, the shops are full of gadgets that you imagine, just for a moment, might be useful until you think about why they can't possibly do anything you couldn't do better yourself. And meanwhile the Universities are being pressed to discover things that have some commercial potential, so that they can prove that having great brains at work is worth the money.
What about the marvellously simple invention that costs nothing at all, and saves you having to buy some gadget or equipment or tool that costs a lot? Something for free that does the job just as well or better? Is that worth inventing? I find myself doing so all the time.

Here's one from this week. "No-bracket bike lights".
The problem: you have more than one bicycle. One of your bikes has battery lights that clip onto brackets fixed to the cycle. Now you need to ride the other bike which has no brackets for the lights (because the lights came with just one set of brackets), and no lighting set of its own.
The solution: (1) clip the back light to your reflective belt, back pocket of your rucksack or back pocket; (2) find one of the red rubber bands that the postman drops. Fold it double and wrap it round the handlebars or steering column of the bike in such a way that there are two loops, one on either side of the bar. Rest the front light on the handlebar or against the column, and pop the two loops over the front and back end of the sausage-shaped bike light. Adjust the tension of the loops by moving parts of the band from front to back or the reverse, until your lamp is pointing roughly in the right direction. Hey presto: hands-free lighting.