Mepper is a general purpose 2D tile-based game map editor. It supports several types of game maps. Mepper supports read/write map/resource using plugins, transit terrain automatically. Proposals/bugs please visit: http://groups.google.com/group/mepper
This programm allows to view gumps from .mul files used by Ultima Online. Additionally it can search for new gumps after an update of the gump files. This allows the users to quickly figure out which new gumps where added.