The Cable Car is definitely wortrh a visit, but it used to be closed in August for maintenance
. I cannot find a mention of this on the website, so things may have changed. August is low season in that part of the world so good deals can be had, if you can stand the heat.
The top station overlooks Palm Springs Airport so you can watch an interesting assortment of traffic arriving and departing from above.
TG.
Edit:
On reflection, I would say that the traffic at KPSP is 'varied', rather than 'interesting'!