We've heard this complaint a lot from people who travel and while we can't verify its level of annoyance, it seems it is pretty high on the list.
Basically, for some of you power people in the world, you require the ability to "shift" all (or a large chunk) of your appointments and/or tasks to different times or days. Certainly a tedious task by any standard and there is no easy way to do it, regardless of PIM choice.
Long story short, a retired IBM 'er had this recurring problem and asked a programmer to write up a solution. The result? Trines Appointment and Task Mover, available in the Marketplace for $9.99.
While a bit pricey, the solution itself seems elegant enough and hey, if this can shave some frustrating work on such a boring task, it could be money well invested.
The app is demoed in the two videos below, so you can get an idea of how it works and what to expect. More info can be found here. Feel free to share your solutions in comments, if you share a similar problem and we'll see about getting a proper WMExperts review up of this app sometime soon, if you folks want it.
[Thanks, Jochen, for the tip!]