Loads for me. I love F1, GP2 and GP3. Although the GP2 cars now sound a lot better than the F1 cars - a situation that can't be allowed to continue for long. I also follow the WEC, as well as a bit of BTCC, DTM and the Porsche Supercup too. Others I enjoy include classic racing (i went to the Monaco Historic GP a couple of years ago) and rallying, but it never seems to get much TV coverage anymore and I haven't been to see it live since the RAC rally at Clumber Park in the snow, which was that long ago Juha Kankunnen was competing in a Celica. Must have been early 90's?
I'm not really interested in motorbikes so don't really bother with Moto GP etc.