LopeEdit Lite is a very capable Notepad replacement which is aimed squarely at programmers, yet could be very useful for other knowledgeable PC users, too.
The program has a built-in file browser, for instance, so it's easy to navigate to the text documents you need, and drag and drop them into LopeEdit. Although if you're creating files from scratch then the tabbed interface ensures that's very easy, too.
A powerful Find and Replace tool, with regular expression support, can send the results of your search to a separate pane. So if you run a particular search, you don't have to browse through the entire document to see every hit, because they're all displayed in a single window: very useful.
There are all kinds of other extras. You can bookmark a line in a document for easy recall later, for instance. A Favourites system makes it quicker to reload frequently-edited files. Detailed statistics are available on every document in a couple of clicks (Words, lines, empty lines, characters (including/ excluding lines), creation time, last access time and more). And a File > Send To option allows you to quickly send the current document via email to whoever you like.
And then of course there are all the developer features.
LopeEdit can open files directly from web or FTP sites.
And there's also a built-in ASCII table; support for various new line types; and a host of useful encoding and editing options.
Please note, if you do need more then there's always LopeEdit Pro. This extends the Lite version with a built-in hex editor, an FTP browser, multiple clipboards, code template support, file and folder compare, intellisense for all the supported programming languages, and more.
LopeEdit Pro is yours for around $32 and you can find out more at the LopeEdit site.