There have been a lot of reports similar to this one lately -- especially in England. I think we are seeing a spate of home-made hot-air balloons being launched by pranksters to see how much of a stir they can make. The only thing in your description which is inconsistent with the hot air balloon hypothesis is your description of speed. But this can probably be accounted for by the fact that you may have thought they were much higher than they were. They may have been only a hundred feet up, but if you perceived them as large objects thousands of feet or miles up, then you would have grossly mistaken their speed.
I'll be back in awhile with a link so you can learn more about these things. They have been responsible for hundreds, if not thousands, of UFO reports over the years.
Edit:
http://www.overflite.com/
http://video.aol.com/video-detail/make-i...
http://ukpress.google.com/article/ALeqM5...
Edit: Well, freezie and katee, despite your mutual enthusiasm for the alien explanation, I know what I'm talking about. I have seen three TV news reports of UFO-mania, all of which were caused by these home-made balloons. As I said, if you seriously misjudge the distance, you will seriously misjudge the speed. This is the primary reason for Venus being identified as a UFO, especially when it is observed from a moving vehicle.
Anyway, it looks like you're here to reinforce your ecstatic hysteria. I'm here to give rational, knowledgeable answers. Here's a calculation for you. Suppose you saw something at an altitude of 60 feet, being driven by a 12 mph breeze. That would have the same appearance as an object at 30,000 feet traveling at 6,000 mph.