Having been reminiscing on the Progress or regression thread, I thought I'd start a new one (mainly for us older ones who remember the slam door days well!). With so many units now in very fixed formations and not interoperable with other units, the days of seeing a "hybrid" or two different classes working together are virtually extinct. (Except pacers and sprinters I guess.) I for one used to love seeing hybrid DMU's which were really common, especially the variation of liveries. Or a blue/grey carriage inserted into an NSE liveried unit, or as I remember, a 309 paired with a 302. I also used to enjoy getting on a rake of Mk2's and sniffing out the odd side corridor Mk1 right at the back beyond the guards van that no-one knew was there so you'd get a whole compartment to yourself. What were your favorites, and most memorable, and unusual? Please share links to pics as well if you can!