Sometimes I want to shake some sense into the people who stop me to talk about my bike. They always focus on the electric motor and the Rohloff. Sure, they're the best you can get, but all the same, they're dispensable. They just help you get there. I could lose both by moving off my hill to some flat place and feel little pain. But that's just the dramatic introduction to grab your attention.
At Christmas last year I wasn't buying a new bike (there's only one bike I don't already have left on my shortlist and it is welded, which is a dealbreaker for me) or even any new components, because after seven years my current bike is fully developed in the direction I want to go, extreme comfort and near-zero maintenance. So I had time to consider all the components on the bike and do something you don't have a chance to do if you're either specifying a whole bike, or buying a single predetermined component or set: this is rank components in order of importance.
Surprisingly, the most important component on my bike, on every high-miler's bike, is invisible and intangible. It exists first and mainly in the mind of the frame designer. It is the fit. If between the purpose for which you intend the bike, the frame, and the components where your hands, feet and bottom touch the bike, you cannot get a comfortable and efficient (in whatever terms you define efficiency) fit, all the other expense is wasted. The fit is actually the genius of the people who design the best bikes; most of the rest is image.
Everyone knows I'm a fan of, in no particular order, Schwalbe Big Apple balloons, the Brooks B73 triple helical spring leather hammock saddle, North Road touring handlebars, VP-191 sealed bearing block pedals, all fitted to a Utopia Kranich crossframe updated from vintage times with modern custom Columbus tubes. It is no coincidence that I also like SKS's P65 mudguards and the Chainglider enclosed chaincase, and that a key consideration with the Rohloff for me is the modesty of its service requirements. My bike rarely goes off the tarmac because even the smallest lane is tarred where I live, so a thin layer of dust is wiped off it once a year and every several years, if it hasn't been cleaned by a heavy rain, the bike might even get washed. I cycle in street clothes and use the bike like a utility bike, get on and ride whenever I want to, never mind changing clothes; my clothes don't get dirty on the bike.
But it's easy in a bike well-developed over time to overlook really useful stuff.
(http://www.coolmainpress.com/miscimage/andre_jute_s_ute_in_use_800pxh.jp)
By far the most convenient of the comfort accessories on my bike is the n'lock, which is a stem that unlocks the handlebar from the steering tube at the turn and removal of a key. That disables the bike; further security is provided by a cable you pull out from the handlebar that locks into the stem, and is unlocked again, by the same key turn. Since I live in a low crime area, that's all the security I need. Very convenient, fast, no bending over the bike and getting your hands dirty with cables or U-locks.
(http://www.coolmainpress.com/miscimage/brooks_leather_and_spoke_grip_800pxw.jpg)
Even easier to overlook is the Brooks leather handlebar grips I use. These are made from thick leather rings held together sideways by small bicycle spokes (it's true!) between cast aliminium endpieces. The whole affair looks and feels rock hard. I cycle in common leather dress gloves, zero gel or other padding, and I must tell you that appearances can be deceiving. Those apparently rock hard Brooks leather grips are absolutely fabulous at keeping all kinds of vibrations out of my hands, which is important to me.
If this post starts you thinking of something on your bike that you are so familiar with that you overlook its real value, let the rest of us know so we can try it.
Right, if we're talking about cycling stuff that isn't necessarily attached to the bike as well, I'll put in a word for the Bell Citi and Metro helmets, which are specific designs for commuters who sit upright on their bikes, and very comfortable. These helmets are more than a helmet, a system, in that you can buy replacement foam strips, a warm liner, a rear lamp, and a mirror that fits a channel on the removable visor, all dedicated to the Metro/Citi system. Or you could when the helmets were in production because Bell, with the mindlessn disregard of customers' wishes too often displayed by big corporations, have taken them out of production. Wearing my industrial designer hat, I can only describe the Metro and the Citi as timeless classics.
(http://www.wiggle.co.uk/images/bell-citi-helmet-08.jpg)
I have the Citi/Metro mirror on my helmets because it works when you have nothing else, but normally I use a handlebar mirror, for which I fancy a roadie's drop bar item made by Cateye, the 300G, because it is cheap and gives you a superb, undistorted view. It plugs into the end of the handlebar, including in drop bars, and I use mine on North Road bars, without space to fit any other mirror, hanging below my gear change hand, where it is well out of the way. I also use it as a sacrificial piece to protect my bike and my expensive grips. It's a fiver at SJS http://www.sjscycles.co.uk/cateye-bm-300g-race-mirror-left-or-right-fitting-prod13904/ which must make it one of the few remaining bargains in cycling, so I don't care if I smash one against the pillared entry to a narrow footbridge at which I usually arrive at near enough 50kph, and where before I switched to the 300G, I smashed more Zefal mirrors than was good for my temper. Interestingly, whereas the Zefal invariably smashed irreparably, the 300G, even at that speed, stands a 50:50 chance of surviving contact.
(http://www.sjscycles.co.uk/images/products/medium/13904.jpg)
Another component that I pay zero attention to because it is fit and forget is a Cane Creek S6 headset copy, made by Cane Creek itself for Humpert in Germany, and sold by Humpert as the Xtasy (never mind, the name is in tiny script) at what I understand is a reasonable price; this headset comes standard on several top German bikes and, according to one manufacturer, no one has ever been known to wear one out or make a warranty claim on it. The Cane Creek S6 is the headset that quite literally created the Ahead-set standard which is today near universal, so its provenance is impeccable. A class act, but silent and nigh invisible.
(http://www.humpert.com/en_script/bikeparts/marke/produktart/einsatzbereich/produkt/download/?produkt=244&bildNr=3)