`Unknown` file download after reload in Safari 8.0 on OS X Yosemite
I suspect it is not an empty file but malware from 'carpet bombing'. Do not attempt to open the file but get info on the file and you should see it is from known malicious sites. I am scanning my system right now using ClamXav and nothing is coming up bad so I suspect it will go away if you just keep trashing the files until the hacker gives up. If anyone knows more than this please contribute.