Multiple file upload inside a form

[eluser]megabyte[/eluser]
OK, so let me further explain so it doesn't sound so obviously simple.

I have a form in a cms, and I want to allow the user to upload multiple files.

I'd like to use flash, but every time I read about it I hear it needs a certain Flash version, and people have struggled to get it working with CodeIgniter.

So what I'm thinking about is using an iframe technique, but havent been able to find one I understand. I don't understand why you couldn't just put the entire upload inside the iframe instead of just posting to it.

Has anyone found a great solution? Implemented one?