From the Soldier side: I like to collect some odd things. I now have over a dozen watches. Most of them work. The ones I prefer are the ones that have the day and the date. Somebody asked me why I prefer a watch with the day and the date. It's because when I was in Bosnia and Iraq, we had a syndrome we called "Ground Hog Day" (like the Movie Ground Hog Day).
So, you needed to look at the calendar each day to figure out not just the date, but the day of the week. For many of my assignments in Iraq, it was really easy to loose track of the day of the week...and after a while, the month.
For example in Fallujah, Iraq, Dec 2004:
0500 hrs: Wake up
0515 hrs: Go to the gym
0545 hrs: Shower, shave and shit, wear the same uniform (a clean one as needed)
0600 hrs: Go to mess hall, eat the same thing
0700 hrs: Show up at the "office" for work, (fixing mess kits)
1300 hrs: Lunch of MREs and a short nap
1400 hrs: More work, fixing mess kits
1800 hrs: Dinner
1845 hrs: Review reports with USMC folks and plan the next day.
2200 hrs: Go to bed
Get up the next and repeat, get up the next day and repeat, get up the next day and repeat, get up the next day and repeat. For 3 weeks.
Fly or convoy to other places and repeat for 4 months. Then change duties.