LDraw files (LDR, DAT):
application/x-ldraw
Multi-part LDraw files (MPD):
application/x-multi-part-ldraw
LDLite files:
application/x-ldlite
The web server munin.nbi.dk [4], which formerly hosted LDraw.org was configured by adding:
AddType application/x-ldraw dat
AddType application/x-multi-part-ldraw mpd
AddType application/x-ldlite ldlite
to the file /etc/httpd/conf/httpd.conf (it's Apache). Most people prefer to use three letter extensions, so the LDLite line should probably read:
AddType application/x-ldlite ldl
For questions, contact Jacob Sparre Andersen [5]