Summer Hiking in the Desert

I'm pretty much a year-round hiker.  This isn't a problem in the Pacific Northwest (unless you have something against walking in the rain...year-round), but hiking in the summer in the desert southwest is a whole other matter.
Unfortunately, many tourists are lured to the amazing vistas in the desert southwest, yet they want to see these sights during their summer vacation.  It's hot as Hades in the desert in summer.  Which leads to deaths (examples here, here, and here).  But it isn't impossible to enjoy the outdoors during the summer in the desert if you take a few precautions:

• Pay attention to high heat warnings.  Believe it or not, there is a difference between 100 degree temps and 115 degree temps.  Don't hike during times of high heat warnings (unfortunate example here).
• Plan short, early hikes instead of lengthy, all-day hikes.  I'm at the trail head at daybreak, hike five to ten miles, and am back to my vehicle by 9am.
• Carry twice as much water as you think you will need and drink often.  You can become dehydrated and not even know it until you feel like you've been hit by a Mack truck.  Drinking water (not coffee, not alcohol) frequently can alleviate this problem.  I also carry extra water to give away as I've run into other people on the trail before who didn't bring enough water.
• Dress appropriately.  Shorts and a tank top may be fashionable but it is a bad idea to wear clothing that doesn't protect you from the sun.  Long pants (which not only protect your from the sun but can protect you from bugs and random cactus encounters), lightweight-long-sleeve shirts, a hat, and appropriate boots are also necessary.
• Don't forget sunscreen, and reapply liberally, as well as sunglasses.
• Bring some sort of food as well (even if you don't usually eat early in the morning, you need to fuel your body for the hike so eat something before you head out and bring additional food with you).
• If you don't know where you are going, go with a guide.  Or at least use appropriate technology to ensure you can find your way back to your start point.
• Hike with someone, if possible, and also email your itinerary to a trusted friend (so if you don't come back they will know where to begin searching for you).
• Be aware of desert dangers (usually snakes, possibly Gila monsters, and even goats).  And flash floods.  Don't hike in desert areas where it recently rained, is currently raining, or expected to rain.
• Bring your emergency kit with you (include compass, emergency blanket, matches, etc).  Example here.
• Other gear to bring: a day pack, hiking poles, a cell phone, GPS device, etc. 
• Study up on the topic of desert hiking.  Or better yet, take a class if possible.  There is a lot to learn about hiking and surviving in the desert and it's better to learn from other's (not your own) mistakes.  A good basic primer can be found here.