A new Mac, and browsing with Safari.
But that's the weird thing, Mike. It's completely intermittent for me as well. In fact, last night, I had actually already downloaded and uploaded files when it quit working. I tried restarting everything too, including a complete reset of the browser, and that made no difference.
I will try the other option though. I don't really feel compelled to use netstorage, I just need something that will work.