One of the tools that I get a HUGE amount from is David Seah's ETP, which is broken into 15 minute increments. It helps me both plan what I want to do with my day, and track what I ACTUALLY do with my day. Then I have a matrix I've put together to track how long specific subprojects/NAs take, because I've found that I have been terrible about estimating how long things take -- and as a previous poster mentioned, so frequently it's the little stuff that doesn't seem like it should take that long, but does! I've now got several manuscripts' worth of timing data -- that'll help me with future project planning!