Vim (Vi Improved) is small, fast, and incredibly powerful. It does have
a steep initial learning curve, but it has an extensive help system. Type
":help" first thing when you start it to read the tutorial. I use Vim for
Kate (KDE Advanced Text Editor) is not quite as small, fast, or powerful
as Vim, but it's much easier to use. It's probably the best "beginning
programmer's editor" I've ever seen. Kate is a standard tool in KDE3.
KWrite doesn't support XML out of the box, but you can choose
Settings:Configure Highlighting:Highlight Modes, change Highlight to "HTML",
and change the File Extensions to "*.html;*.html;*.xml", and it'll highlight
XML just fine.
KWrite's not powerful, but it's fast.