Programmers are very passionate about which text editor they use. There are many lists of the top 10 text editors available for Windows, OSX and Linux.
During my PhD, I had to become very familiar with coding and scripting. I need my text editor to be able to perform complex, multi-line regular expression searches. And as a student, preferably, the text editor would be available for free.
I discovered Notepad ++, which I fell in love with. It was very easy to use, and made me feel very comfortable. But, I soon discovered that Notepad ++ was not very good at multi-line regular expressions. This was a deal breaker. I started looking for a solution. Unable to find one, a colleague nudged me towards XEmacs. It took some getting used to (and configuring), but once it was set up, I could use it to get my work done (although I wouldn't say that I enjoyed using it).
When I started working as a Research Officer, I was handed a MacBook Pro and needed to find a suitable OSX editor. After some detective work, I came across Smultron, which I immediately liked nearly as much as Notepad ++. I created a Praat syntax highlighting scheme for Smultron, but when I read that it was no longer being developed or supported, it made me think twice about relying on a no longer supported application. I decided to keep looking.
And then, it happened. I came across Aquamacs. Aquamacs takes everything you hate about Emacs and fixes it, making everything you love about Emacs multiply tenfold. You just download and install it and it just works, without losing any of the awesome power of Emacs. It is hands down the best text editor I have ever used, and reason enough to sell your Windows machine and purchase a MacBook. It is that good.