I drive a 1991 Red Defender so I always wave an usually get waves back. My girlfriend now waves franticly as other defenders pass too. I also have to admit to driving round Morrisons car park looking for another defender to park next to, there are a fair few round here so I usually get lucky.
My Dad now owns a Disco 3 but hes had Land Rovers (of the Discovery type) for many years so understands the need to wave at other Landy divers. The Defenders usually seem to be quite surprised to find themselves having a Disco 3 waving at them. I never personally like the Disco 3 until I drove one, then I could understand why they're popular. Its just a shame they go to too many of the non-Landy folk now. I'd still prefer a Defender anyday though. So much road presence...