Slickedit is great for navigating large blocks of code you don't know. The tags feature allows you to deal with the code on a functional basis, without having to deal with which file is it in. (EMACS actually has tags and is every bit as good as Slickedit, but with a slightly steeper learning curve)
When you get to a method or class or variable you don't understand, you just push-tag to go to that code, look it over, then pop-tag back. (those are bound to keystrokes, so it is very quick)
You can also use find-references to see where that function/variable is used.
Saves tons of time over having to go and figure out which file something is in.
