I couldn't help but notice the time variations from weeknights to weekends. That's not good for your health, according to some research. I've heard that in news reports in the past, but I don't recall the ill effects it supposedly has.
Here's just the first thing I found on the net:
http://my.clevelandclinic.org/neurological_institute/library/know_sleep.aspx
An excerpt:
Tips for a Good Nights Sleep
Create an optimal sleep environment by making sure that your bedroom is comfortable, cool, quiet and dark. If noise keeps you awake, try using background sounds like white noise or earplugs. If light interferes with your sleep, try a sleep masks or blackout curtains.
Think positive. Avoid going to bed with a negative mind set, such as If I dont get enough sleep tonight, how will I ever get through the day tomorrow?
Avoid using your bed for anything other than sleep and intimate relations. Do not watch television, eat, work or use computers in your bedroom.
Try to clear your mind before bed time by writing things down or making a to-do list earlier in the evening. This is helpful if you tend to worry and think too much in bed at night.
Establish a regular bedtime and a relaxing routine each night by taking a warm bath, listening to soothing music or reading. Try relaxation exercises, meditation, biofeedback or hypnosis.
Wake up at the same time each morning, including days off and vacations.
Stop clock watching. Turn the clock around and use only the alarm for waking up. Leave your bedroom if you can not fall asleep in 20 minutes. Read or engage in a relaxing activity in another room.
Avoid naps. If you are extremely sleepy, take a nap. But limit naps to less than one-hourno later than 3 pm.
Avoid stimulants (coffee, teas, cola, cocoa and chocolate) and heavy meals for at least 4 hours before bedtime. Limit caffeinated beverages to two per day and avoid them entirely if you have trouble sleeping at night. You may find that light carbohydrate snacks such as milk, yogurt or crackers help you fall asleep easier.
Avoid alcohol and tobacco for at least 4 hours before bedtime and during the night. You may find that you will fall asleep faster and awaken less often.
Exercise regularly, but not within 4 hours of bedtime if you have trouble sleeping.