If you are usin xp a zip file opens just like any other file
Though that could run into problems when working with the files, lol. What file system is that thing using? That many small files might be eating up all the space even though they are very small simply due to wasted sector space. I'm not sure exactly how flashdrives handle filesystems but if it is anything like an hd that might be your problem. When you select all the files, right click, and hit properties what does it say for both the size and size on disk?
<A HREF="http://www.folken.net/myrig.htm" target="_new">My precious...</A>