As part of a recent project, I was tasked with taking timestamps returned by an API and displaying fuzzy dates in the final output (e.g. 3hrs ago, in 2 weeks, tomorrow). The timestamp format in question looks like: 2012-09-01T16:20:01-05:00 This format can be found in PHP as the DATE_ATOM or DateTime::ATOM constants, which contain the date() formatter string: Y-m-dTH:i:sP With this in hand, we can now easily parse the timestamp into a useful object.
Parsing the date into a DateTime object is as easy as giving it the date string and telling it how it's formatted. Then you can do all sorts of fun things. He shows how to shift the timezone by name, by time increment - simple (like "1 hour") and more complex (like "1 hour 5 minutes 3 seconds"). You can find out more about the DateTime object in the PHP manual.