What are any good summer programs for computer science or math or engineering/technology that look good on college apps?
Go because you think the program looks interesting and/or fun, not for college app purposes. A summer program does little except show colleges that you could pay for an experience most of the time. That said, if you learn something – new skills, more about careers, get clarity on what you do and don’t want to do in college and beyond – then it is worthwhile. If you are female, look for Girls Who Code programs. Another program good for both genders is Operation Catapult at Rose-Hulman.
Anything you would do regardless of whether it would look good is likely to look good.
Anything that you do primarily because you think it would look good is unlikely to look good.