Early morning rides are the only solution for my daily workouts. I have to get up at 5 AM in order to get 10 miles in and back home to get ready for work, get the kids up for school, etc. I could do it in the evening but in the summer (especially this summer) it's just too darn hot and I'm usually tired from work and don't feel like getting on a bike. Plus it takes away from family time. On Saturdays I like to take off in the morning and do whatever ride I planned on doing that day.
If I didn't have this pesky job to contend with, I'd do my riding at around 8 AM or so before it gets too hot.