I don't know if it's still there, but there was a Curves on Ditmars Blvd. I think it was between 32nd -33 Streets.
I'm a member of the Rock and I love it. It's well run, with great classes and equipment.
They do participate in one of the insurance programs - I think it's Global Fit. Also, if you can pay upfront in cash, they will give you a cash discount. I do this and it works for me.
They also offer discounts when you belong to certain unions - I think SAG, firemen, police, and maybe teachers, but I'm not sure about whether they still offer this.
If you have more questions about, feel free to PM me.
There's also the new yoga studio on 31 St., The Giving Tree. It's run by a former Rock yoga instructor and her husband. You could opt for a series of their classes and get some home equipment to supplement.