Loretto Chapel, Sante Fe.
http://www.lorettochapel.com/history.html Sante Fe is a great place for art and NM history. The Georgia O'Keeffe Museum also a must see.
Los Alamos, NM.
http://visit.losalamos.com/home.htm More of a reason to ryde NM 4, a great motorcycle road.
Taos, NM.
http://www.taoschamber.com/ US 64 from I-25 west to Chama is a beautiful road, as are most of the 2 lanes in this area.
The National Radio Astronomy Observatory.
http://www.nrao.edu/ As seen in the movie Contact. Quite a bit out of the way. An alternative to I-40 west to AZ. US 180 in NM and US 191 across the line is a great road.