I have an app that instructed me to copy some data from my computer to the SDCard. So I plugged the Droid into the computer, mounted my Droid SDCard, looked at the directory, and copied the file. There are a bunch of files and folders listed (e.g. backups for apps, album artwork, etc.) as being on the SDCard. But when I go into Astro on the Droid and select "SDCARD" it shows "directory is empty." I don't get it. Why can't I see the folders and files on the SDCard that I can see on the computer screen?