I've seen lawn tractor racing on Speed Channel before. Its pretty funny. I just have a 17hp, 42 inch cutting deck on my tractor.
But, to be honest, I'd much rather have one of these:
Mitsu tractors are kind of hard to find in the US. Plus they have diesel engines and are not quite as practical to use for just lawn mowing duty. But I still want one.
later,
Curt