All complex software inevitably has a swag of useful little features that whilst great aren’t that discoverable. After recently seeing several different people switching to their IDE and manually opening a file to dive into a source file they were looking at in Fisheye or Crucible, its clear that the open in IDE links fit firmly into the “non-obvious feature” category.
So if you haven’t discovered it yet, you may be interested to learn that you can “one click” open stuff in your IDE from Fisheye & Crucible. Easier to see it in action than to try and explain it:

To get these shortcuts to show up, all you have to do is have Eclipse or IntelliJ IDEA running with the free Atlassian IDE Connector installed.
UPDATE: Its just been pointed out to me that IDE shortcuts are available in Bamboo now too!

Protip: Open in Eclipse & IntelliJ Shortcuts