Patio/gazebo windows?

Question:I'm looking for ideas on what type of windows I could put on my enclosed patio/gazebo to keep rain and snow out, but I could open in the summer. I need inexpensive options, and they have to be able to resist a little bit of frost heaving in the winter without breaking!

Answers:
How is your patio/gazebo enclosed?-- screening?
I had a patio I was considering inclosing but also wanted air circulation-- I asked my brother ( who really does know nearly everything!). He suggested recycling patio doors-- with the screens. Sounded good to me.
However, I must report that I sold that house before I did the deed.
good luck