Ninja UV (formerly KAM mapper). http://www.creativecrash.com/maya/marketplace/scripts-plugins/texturing/c/ninja-uv--2 it costs $25 now, but it is a great script, and the author is always adding cool new features.
Depending on your Maya Version there is "LevelTools" or "LayoutTools", which are meant to help with Level Design. 8 and lower : http://area.autodesk.com/downloads/plugins?word=level&where=1&software=8&script=&os= 2009: http://area.autodesk.com/downloads/plugins/leveltools_35 2010:…
I recently joined a studio who uses maya for their levels and environment work, I am switching from 3ds max and am wondering if you could list any useful maya addons/user content, such as: Scripts Toolsets shelfs curve tools UV tools Or information that might help me make the jump from 3ds max to maya, or anything related…