One thing a lot of folks pass by is Acoma Pueblo, also known as Sky City. You take an exit just a bit east of Grants, and the road takes you south to the bottom of a mesa. So far as I know you can no longer drive up there, but it's a nice half day visit (or more or less, depending on your tastes). It's a very interesting pueblo with an interesting history.
The Sandia Tram (Tramway road north of ABQ) is a nice ride to the Peak (Sandia Peak) and there's a restaurant there, too. Or take I-40 east of ABQ into Tijeras Canyon and take state highway 14 north to the Sandia Peak turnoff -- there's a very nice view from the Peak (at the "Forest of Steel" -- antenna farm), both of Albuquerque and of a huge chunk of the surrounding area (further than you might think). It's a bit of a (level) hike to the tram and restaurant, though.
Bandelier National Monument is northwest of Santa Fe (cliff dwellings, slightly different from those at Mesa Verde), and the NRA's Wittington Center just south of Raton (if you're a shooter -- fabulous ranges). There's a nice aviation museum at the Pueblo, CO airport, and Colorado Springs has a number of things, including Seven Falls and Garden Of The Gods.
Just over the Colorado/Wyoming border is Terry's Bison Ranch, which includes an RV park and a playground for kids, along with a small train ride (in season) and a sort of zoo, with unusual animals you can get close to, even touch some. Downtown Cheyenne has a nice railroad museum in the Depot, and there's a (free, donations requested) horse carriage tour of parts of Cheyenne. There are also a couple of "Old West" museums, one at the Frontier Days complex.
No doubt I've left out a lot, but those are what I can think of offhand.
