I am not the worlds greatest window washer! There are always streaks. I have found that squeegees work great! For my outside windows, I fill a bucket with soapy water. I use the sponge side of the squeegee to "wash" the window. I then spray it off with the hose and then use the other side of the squeegee to get all the water off. It works great, with no streaks.
I also use a squeegee in my shower. After every shower you just squeegee the shower door and you're left with nice clean doors. No soap scum and no water marks.
A squeegee works for me! Hop on over to We are THAT Family for more Works for me tips.
**NOTE** The machine I posted on a few weeks ago for transferring my videos to DVD's works great! I also tried the Yummy Soup application that someone else posted on and love it.