Deprived
For me, the optimal amount of sleep every night is around eight hours. Seven is OK, but anything less starts to impact all sorts of aspects of my perfomance. The kids have currently adopted a rather unbebeneficial sleeping schedule, going to bed around eleven, give or take half an hour. I tend to have some mandatory stuff left to do after the kids have gone to sleep, so it's usually at least half an hour later when I go to bed. I get up at five, you can do the math.
I am fortunate in riding my bike to work, as keeping alert on a bike is much easier than in a car. Fresh air and direct contact with the world around me (as opposed to being enclosed in a steel-and-glass shell) helps a great deal. I also learned a very simple trick in the military: (Finland has conscription.) If given a choice between eating and sleeping you always eat. The reason is quite simple: You can survive a great deal longer not sleeping than you can not eating. Basically you always have to eat more if you sleep less (more time spent doing stuff, so a greater amount of energy is consumed).
I don't plan on keeping this up for long. My summer vacation (4 weeks!) starts in less than two weeks, and I'm going to reevaluate my schedule when I return to work; unless the kids have changed their sleeping habits by then. The most important thing is not to let it get to you, and keep in mind it's only a phase. I'm sure this will be all forgotten and I'll have a whole array of new issues to deal with soon enough!
I also found a rather interesting BBC article on sleep deprivation, as well as a whole site on the subject. That's all folks, good night!
PS. Given the current circumstances I have less than my usual amount of energy to dedicate to blogging. I will probably update less often in the near future, as I'd rather keep the quality of individual posts high than post a lot of... well... crap.