My day job involves working on an OSS project called Max Media Manager, written in PHP.
The project involves the collection and presentation of statistics, and thus, dates and times are rather important. Ideally, we want to record all dates and times in the database in UTC, and then simply adjust them according to user preference (ie. show them in UTC if they want, or change the times to be in the user's time zone, so the statistics make sense to the user, wherever they are in the world). However, the project is a fork of a previous OSS project, and as a result, the UI doesn't have separate data access and presentation layers yet, so this goal is a little way off.
