As I'm switching from Windows to Ubuntu/Gnome, I'm looking for an alternative to UltraEdit.
I tried a few tools, but they often lack some really useful features, such as:
Which one do you use? And what are their major features?
Kate supports syntax coloring and lots of charsets. I'm not sure what you mean by "ftp edition of files", but kate also includes a console, so you could use ftp from there.
geany is a lovely editor, but it uses GTK+ and not GNOME, so it doesn't have gnome-vfs/gvfs integration. bluefish has the gnome-vfs/gvfs integration, but is a bit on the buggy side. gvim is a bit harder to use and doesn't support FTP directly, but is very extensible. In the worst case you could use FUSE to mount the FTP directory onto your system.
In the spirit of cross-platform editors, I'd like to point to Scintilla and SciTE. Implementations are used in many IDEs and editors, available for Windows and Linux.
SciTE is a SCIntilla based Text Editor. Originally built to demonstrate Scintilla, it has grown to be a generally useful editor with facilities for building and running programs. It is best used for jobs with simple configurations - I use it for building test and demonstration programs as well as SciTE and Scintilla, themselves.
SciTE is currently available for Intel Win32 and Linux compatible operating systems with GTK+. It has been run on Windows XP and on Fedora 8 and Ubuntu 7.10 with GTK+ 2.12
Scintilla is a free source code editing component. It comes with complete source code and a license that permits use in any free project or commercial product.
As well as features found in standard text editing components, Scintilla includes features especially useful when editing and debugging source code. These include support for syntax styling, error indicators, code completion and call tips. The selection margin can contain markers like those used in debuggers to indicate breakpoints and the current line. Styling choices are more open than with many editors, allowing the use of proportional fonts, bold and italics, multiple foreground and background colours and multiple fonts.
I just use plain old gedit. It has syntax highlighting and handles charsets.
For handling files on FTP shares I just mount them using the Places->"Connect to Server" functionality and then the remote files are easily accessible from gedit (or any other Gnome program for that matter).
Do not look for FTP support in applications. This stuff is better handled by the system, using FUSE file systems or Gnome VFS, etc.
If you want to be hardcore, and want to pick up a semi-useful skill, look into learning vim (or a variant such as ultra-hardcore vi, GUI gvim, etc.); vi and its siblings are the most widespread installed editors on *nix boxes- you might find yourself in a situation where the only editor available is vi.
Otherwise, I would suggest using something that supports the language you use- i.e. I'd rather not program Java without Eclipse.
For other stuff, I use joe, which is a very small and nice command-line editor with Wordstar key bindings.
Ultraedit is now available for Ubuntu. It's commercial, but fairly cheap and there is a free trial.
http://www.ultraedit.com/company/blog/products/ultraedit-for-linux-released.html