I'm very finicky about having clean, streak-free windows too. For the outside of the windshield I use the same type of squeegee and net sponge you see at gas stations (pic below) and keep it in a bucket of clean water in the utility sink in my garage. After use, I run the net sponge under the faucet for 10-15 seconds to clean it, then place it back in the bucket. For the excess water around the edges, I use a microfiber auto cloth that's available from Costco in a pack of 36 towels that will probably last me a lifetime since they are washable.
For the exterior of the other windows as well as the interior of all, I also use Stoner's "Invisible Glass" and the same microfiber auto cloths. Works like a charm.
Amazon carries the squeegee I'm talking about for $10 and change.
