You may also consider "Searchable Fields by Anton. This is a hack rather than a module and it worked when I tested it on Cheetah if I recall.
I'm using it on my main site it's great.
Say you have a multi select field called Musical Interests with a choice of ten items. When a person ticks Rock, Blues, Jazz, those items will appear under Musical interests in their profile. If a viewer clicks Jazz which is now searchable as a separate identity, they will receive a list of All members who also selected Jazz.
This way a member can choose as many genres as they like.

the project I am working on now is for a record company that my son is starting. it would be nice to just use the existing categories and rename it to genres. this way it becomes searchable. If not, then I have to figure it out. But you are right, I can just create a new field called genres, and edit a file to make it searchable. I have just found many instances where it would have been better if categories was already a part of the profile page.

Why categories?
It's a profile.
If you want to categorise, get them to do that at sign up.