I've been trying to find a way to keep my appointment times from moving around on my calendar as I change time zones.  Here's a description of the problem from Microsoft (edited to match my situation):

You are traveling through multiple time zones and need the calendar to display the local time for each appointment. For example, imagine you are in New York and have a breakfast meeting at 8:00 A.M., then fly to Chicago for a 1:00 P.M. meeting, and then fly to Las Vegas and have a dinner reservation at 6:00 P.M. Outlook displays all these appointments relative to the time zone you were in when you created the calendar entries. This means that in New York when you look at the Calendar, breakfast is at 8:00 A.M., the Chicago meeting is at 1:00 P.M., and the Las Vegas dinner is at 6:00 P.M., but when you look at the Calendar in Chicago, the breakfast is at 9:00 A.M., the local (Chicago) meeting is at 2:00 P.M., and the dinner is at 7:00 P.M.

(Adapted from http://office.microsoft.com/en-us/outlook/HA010565301033.aspx)

My Palm Pre does the same.  I think I have fixex for both.  We'll see after my trip this week.

For Outlook, the fix is to disable automated time sync in Windows (I know this fix works).  To do this in Windows 7, click on the clock, click Change Date and Time Settings, click the Internet Time tab, click Change Settings, and uncheck Synchronize with an Internet Time Server.  (I undo this when I get home.)  Then change the clock manually when you get to your destination.  This will keep your time zone from changing.  In my case, this means that the dinner I put on my calendar for 7 pm won't move itself to 10 pm.  But it does mean that I need to watch out for web sites that automatically add calendar entries using the local time zone and manually change those to the local time (for instance, Open Table puts a 7:30 pm. EST dinner on the calendar at 4:30 PST).  Fortunately, that's the less frequent problem.

For the Palm Pre the fix is easier: Open the Date and Time app in the Launcher and change Network Time Zone to Off.  The time will change when you travel but the time zone won't.  (At least, that's the theory.  I haven't tried this yet.)