Back when I was doing marathons (and walking them, I might add), I was always very conscious of what paraphernalia I needed to take on the training walks with me. With marathons, you are on a training schedule where you increase the lengths of the runs/walks as you get closer to the race. When you are out there walking for upwards of one hour (two hours, three hours, four hours, maybe even five hours) you need to take some stuff with you. When I am out there that long walking around, I need to have tunes, a phone, snacks, and water to drink. A sweater if it is cold. Yadda, yadda, yadda. So I would be walking around with a pack full of things, and that can weigh you down.
Now today, if I were training for a marathon (and I do hope to do at least one more) I would look into buying a new phone such as the M800 cell phone (Buy the M800 at www.cellphoneslord.com )that is really a cell phone and watch in one. (You need a good watch, because as the hours roll by, you really need to know the exact time!)
It just boggles my mind what the M800 will do. It has an MP3/MP4 player, with bluetooth stereo headset, and it is also a speaker phone. It has a touchscreen, the Internet, an alarm, and anything you want, basically! Plus it tells time.
I just can't tell you how much this would enhance marathon training and a marathon itself. Music is very important to me, and with this watch, I could listen to the tunes that would make the time fly by. And it would certainly cut down on the paraphernalia I would need.