I'm WebPlug's No. 1 fan, I hate HTML without it, it's a shame the author left the amiga a couple of years ago. It makes writing good HTML easy, and it's multiple document handling means that it's easy to work on a whole site in one go.
I run it on it's own screen (1024*768) with all the various toolbar windows around the edge for maximum efficiency.
The only problems are a couple of bugs in the 2.0Beta and the syntax hilighing is a bit basic, although as it is a plugin type system someone could always make a better one.
It's sad that it's often overlooked. A real hidden gem (and in my top ten most wanted OS4 apps.) :-D