Copyright 2012, Michael A. Jackson
Attribution 3.0 Unported (CC BY 3.0)
http://creativecommons.org/licenses/by/3.0/
Two ArcToolbox tools, one for tables and one for feature classes. Create a new dataset with the order of fields sorted. There is an additional option to put a subset of fields at the front. Uses arcpy (ArcGIS 10.0 or above).
ArcGIS Resource Center:
http://resources.arcgis.com/gallery/file/geoprocessing/details?entryID=977F8B9B-1422-2418-A012-7EFD1F2EDB16