I work for a small-ish company, 70 people or so, 10 of us are developers. Every month we submit a timesheet tracking the hours spent on the projects we're involved in. Because we leave this until the last minute, we spent up to an hour going through our daily svn commits to reconstruct the hours spent.
This is clearly a waste of time, I'd be interested to hear of a "system" that works in other organizations. Maybe it's just a case of being disciplined to complete a paper timesheet every day, but I'd prefer something electronic and unobtrusive.