How do you people go 2 hours on the trainer in zone 2 without your head esploding from boredom?
After an hour and a half with mixed intervals I'm ready for the loony bin.
I also do single leg drills, high speed cadence work, and total failure efforts on the trainer, as it is safer than on the road. No worries about what's going on around you, or terrain changes that mess with effort.
I like the GCN workouts, and CTX has a few good ones too.