Well, after fighting with VB for a full two days (God, I hate that language! hehe), I wrote a little program for taking files to the car. I don't know how useful this would be to people, but it is for me, so I thought I'd share.
The raison d'Ítre for this program is as follows. Suppose you have all your files in C:\Media on your car. In my case, I have C:\Media\Music and C:\Media\Videos. Now, I want to add a couple of new albums to C:\Media\Music\Goa, \Eurobeat, \Trance, as well as a few to \Videos\Music Videos. This application simplifies it.
First off, you must have Autoplay enabled, and your shell must be Explorer, and the Autoplay function must be enabled (the one that pops up the "what should I do with this type of media" box), and you must have .NET Framework v2.0 (thank Microsoft for requiring 20MB of libraries for a 40KB program). Download the two attachments, AutoPlay_Editor.exe and MobileFileCopier.rar. Put MobileFileCopier.rar somewhere, and use Autoplay_Editor to add it as a default handler for Mixed Media, Audio Files and Movie Files.
Next, put the files into a subdirectory on your removable media. Note: root directory is NOT supported (I believe in using flash memory for things other than just shuttling files, so it requires a subdirectory). So let's say in my case, I would create the following structure on my flashdisk:
and put all the files in it (with subdirectories, whatever, as you wish).
The first time you plug in your removable disk, a setup box will pop up, which will ask you where you store your media on your hard disk, and where you store media on your removable disk.
Then, when you plug in the flash disk into your car, it will automatically copy everything inside the \Media directory to C:\Media, or whatever you chose. This will work for multi-drive flash readers, USB keys, CD-ROMs, etc.
If you keep using the same folder on your removable disk every time you plug it in, it will never ask you for that information again, and just copy everything automatically.
You can hit the big STOP button if you want to abort the process. Note that it will only abort as of next file, since I couldn't figure out a way to tap into the file copy process mid-file.
Comments welcome. I hope this is useful to you, but I do acknowledge that, considering all the prerequisites, the chances of anybody using it are quite slim