Slowly making the transition away from UltraEdit to Notepad++. UltraEdit is awesome and has been my main editor for probably going on a decade now. I've bought 3 upgrades.
Unfortunately it doesn't play nice with the revision control system at work. It takes a while to exit after editing a file during an interactive resolve session. And by a while I mean longer than Outlook! Outlook is notorious for its process taking forever to exit after you've exited the application.
Anyway, I'm finding all sorts of nifty stuff with Notepad++. Like being able to stuff a string into a bunch of lines at once. Alt-Click-drag (column mode) across the text you want to replace on all of the lines and start typing - presto! The text is inserted at the same location in all of the selected lines! Great for manually transforming text from copy/paste across different systems.
Another nifty feature is the highlight every word that matches the currently selected word. Great for finding things in log files.
Unlike UltraEdit, which threw everything but the kitchen sink into the app all at once, Notepad++ seems to be relatively minimalist. It relies on extensions to add extra functionality. So, for instance, when I wanted to navigate back and forth from whichever file and line I've been at previously (CTRL+-/CTRL+SHIFT+-), I was disappointed that it wasn't built into the app. My disappointment was premature - just looking up that plugin (there's a built-in minimalist plugin manager) exposed me to all the other plugins out there. The plugin (Location Navigate) installed quickly and worked immediately.
I still keep UltraEdit installed, mainly for things that I don't know how to do in Notepad++ yet. But that list is diminishing. And Notepad++ has already replaced it as my %EDITOR%.