The Velo answer to duct tape, these little plastic straps are the ultimate weapon in the war to securely attach bits and pieces to the whole. However, I was surprised to count 18(!) on my bike, holding the necessaries in place (in other words, no "rack" or "pannier" related attachments).
From front to rear:
3 small to attach cyclo-puter magnetic ring to front wheel hub via spokes
4 small on fork for securing the pickup and pickup-wire
1 small for securing pick-up wire to stem shift derailleur cable while on its way to the cyclo-puter
2 (1 med. and 1 small) for a loop to "loosely" guide the rear brake cable away from bell at front of handle bar during turns.
1 med. for "extending" the bell's bar clamp (made for a smaller dia. bar)
1 med. for "guiding" thicker-than-spec derailleur cables at a right angle to the down-tube braze-ons
2 med. at rear of saddle to provide "loops" for attaching a wedge bag
4 small at pedals to hold on a total of two reflectors
Is this typical.. off-the-chart.. or not even close to the limit of what can be done with these miraculous little securing straps? Show us your tie-wrap list and be counted!
That sounds quite a bit higher than usual. The pedal reflectors and bell are probably not commonly used by most road riders so that would reduce the count considerably.
I use 4 to 6 to route cyclometer wires depending on the bike but that's about all. They do have a lot of household uses however and I keep bags of several sizes around.
I guessed that my count would be on the high side. Good point about all the "peripherals" that use addl. ties. My using items that are not the "correct" piece (like my pedal reflectors) also adds to the number.
An imaginative application (like creating a loop for the rear brake cable to move through the fork's turning arc and stop just shy of the bell) is particularly satisfying.
Having worked on cars for years, I know to always have a selection available - their versatility just never ceases to amaze me.