Neat idea for a thread. I might be stretching the rules a touch with these two as they were purchased as framesets, but they certainly aren't stock and I'd consider their use 'reimagined', for my purposes at least.
First is a '71 Raleigh International that had heavy 're-imaginations' from gugie: canti bosses added for 650b, fork re-raked for low trail, custom low-riders and stainless racks, rear brake bridge replaced w/ fender mount, internal wiring for generator lighting (need to get on that), etc.
It's equipped with a mix of Shimano seatpost and hubs, Velocity rims, Suntour XC-Pro derailleurs and barcons, IRD freewheel, Sugino AT triple w/ Sugino rings.
This '83ish Woodrup is in the process of being reimagined for mixed surface use, last step is 28mm-ish rubber up from the 22mm-ish shown.
Mix of DA-74xx with a wide range double on Stronglight crank arms.
And more in-line with the letter of the thread guidelines, this was bought by my father when new and I've slowly replaced everything except for the BB and crank arms at this point. The rest being replaced over time with XTR 8sp stuff (though 7sp cassette and levers) plus a Ritchey/Nitto stem/post and Bontrager bars. In comparison to the two builds above, the overall usage for the bike was not 're-imagined', though parts were swapped.