I spotted that the original post did mention older cars. Sadly I wasn't old enough to photograph them in period, but there are strong retro rallycross series in both the UK and Europe, so a lot of my favourite classic rallycross cars can still be seen in action. Few faves...
My favourite retro rallycross car (and the car I have probably taken more pictures of than any other in recent years!) is "Rosie", the Ford RS200 owned by Pat Doran. Pat competed in this car in the 90's and early 00's, now it is used occasionally by Pat and his son Liam who drives the car a lot harder.