One bit of nostalgia for me was visiting the airport very early on a Saturday morning, probably in 1980.
After accompanying my sister through check in and waving goodbye to her at security, I wandered up to the top of the Terminal 3 car park at about 7am and was delighted to see the Kar-Air DC-6 thundering down 10R (as was), the only one I ever saw there (apart from the 50th anniversary flypast which I saw from Osterley). The day was further enhanced by the arrival of a Fred Olsen Electra, first I'd ever seen.
I missed the heyday of the propliner...