Boulder, Co is no longer affordable. Most likely the reason it is no longer on this list. The average house price is $668,000 and the average rent $2,600. I used to pay the same in rent while living on Wall Street in NYC for a one bedroom corner unit apartment.

A mountain view in Seattle or Portland might be a bit pricey. SLC and Boise are right on mountains, and are more rustic inter-mountain west cities (like Denver and Boulder I guess).

There is also Idaho Falls and Los Alamos, which both host major DOE labs, I think, that would attract tech activity.

After leaving Tektronix in Portland, my Dad moved further in tech at Hanford. The mountains are not so big in Richland, however (well, we lived on a small mountain when we were there).