compression utils, Winzip for Windows Systems - Bzip(gzip) for Internet and other OSs ... simply because they're native, but then again i find them both more stable with larger archives - they don't tend to corrupt as easily.
as for the program, could there possible be more in the way of a gui - i know it isn't too fast in DB, but i prefer to work from a toolbar with a button for camera movement, having it on all the time is confusing (and feels weird)
plus it crashs if there are no textures and you press ',' so you may wanna sort out something to make sure you can't access the texture areas and such if there arn't any.
apart from that, this could grow into something more powerful like 3DMapEditor
earli days though
Within the Epic battle of the fates the Shadow and the Angel will meet. With it will harbinger the very fight of good vs evil!