As I note below, RescueTime is an excellent app for this. It's very fine grained, automatically keeps track of every program you use and website you visit separately down to the second, and requires basically no interaction to run except to check up on yourself at the end of the day; if you tell it which activities/websites are productive it'll also tell you how much of the time you're actually working, and how that gets distributed about the hour/day/week/month. (It probably goes up to year as well, but I haven't been using it long enough to check.) Overall I am very impressed with it.

At MIRI we use Harvest to track employee and contractor time, and it's been largely successful.

We track our time against different projects and have one General project that we use when we aren't working on something that makes sense to create a separate project for. One of the reasons we decided on Harvest is because their reporting tools are really great, which is important to us. The other one is that even though it's fairly powerful, the interface is easy to work with.

My preferred way to use their system is with timers. When I start working each day I start a timer on our General project and process my inbox and figure out what I'm going to work on for that day. After that, I start timers as needed for the various projects I end up working on. With their apps it's really easy to switch from one timer to another and add a new timer so I haven't found doing so to burdensome. Timer are also available through their web app which is nice.

Their exporting functionality is quite robust as well so you don't have to worry about having your data locked in.

I'd also have a look at Freckle. They were my number one choice in terms of user experience, but they lacked a feature we needed (though I can't remember what it is anymore). Looks like they have made a lot of improvements since last I checked.

I wrote a simple text parser which understands semi-free text like

2013-10-17

10:00

$P_1$ +30m reading lesswrong

$A_1$ +1h project A: implementing feature 1

includes discussion with Pete

12:00

-15m lunch break

+15m dicussion about new feature 2

This allows me to take notes with extremely low overhead. I just switch to my programmers editor and write down a few more lines. No opening window, not clicking or tabbing thru redundant fields.

And I can do so incrementally. The $P_1: token assigns the cost center and I usually assign these at some later time batching related items quickly and possibly creating the cost centers after the fact - which is usual at the beginning of a project. The cost token is looked up via a comparable file describing the hierarchical structure of cost centers.

When I started this it was intended to just track time for myself, but it developed into a tool which can push the data into Jira (via REST) and Kimai (via SQL) and export selected sub hierarchies as TeX reports for invoices.

But it is still a simplistic undocumented CLI tool run from my IDE with lots of idiosyncrasies, so I wouldn't recommend it for anybody else.

I believe that it (i.e. the use of plaintext) is a lot more efficient and powerful than a spreadsheet.

Usually I think it is to be a headache for deploying spreadsheets, linking it to other stuffs. Rather I prefer using an automated time tracking software from Replicon ( http://www.replicon.com/time-tracking-softwares.aspx ) which works with a click and ultimately the the automated process gets inclined with.

A bunch of Quantified Self people use Google Forms. I think it's probably an improvement about OpenOffice spreadsheets.

I have been using this app for about 6 months:

Pomodoro Calendar

I have found it to be very, very beneficial in terms of my productivity and focus*. It's based on the pomodoro technique, which follows the basic pattern of working in 25 minute chunks. Whenever you do a work chunk, it can be automatically synced with google calendar. At the end of the day, it's easy to see how many work chunks you have done. Additionally, it can be set up so that you can easily create preset categories for the type of work you are doing. I have categories for different projects at work, hobbies, and exercise. Before I set the timer, I simply select which category I'm doing my work in, and then hit go. When I look at my google calendar, I have an honest breakdown of how I'm spending my productive time.

A word of warning - the app is a little rough around the edges. Every now and then (twice a week?), it will crash, and syncing with google calendar requires a little troubleshooting to start. This wouldn't be that difficult for anyone on LW, and once it's set up, syncing takes care of itself. Crashing is an insignificant issue, and at worst means you don't record the work done during that chunk.

*I now measure my productivity (or at least my work ethic) in how many chunks I have done in a day. I do substantially more now than when I first started, which could be partly because I have gotten into the habit of measuring myself. Still, I feel that I am actually working more. If anyone has any suggestions on how I could more fairly compare my productivity now vs. in the past, I'd be happy to give it a try.