That is incorrect my friend. There are many Linux exploits for metasploit, and they are all very reliable as long as the target application is a vulnerable version. There aren't as many OSX exploits in metasploit, but there are a few. You can add new exploits from places like exploit-db or packetstorm, but you'll have to know how to add them to the framework. There are websites for 0-days...however, they are not released publicly. For example, ZDI (zerodayinitiative) is one such site, but the exploits are only published to the target vender so they can make a patch. If you're looking for 0-days in the wild, you'll either need a lot of cash, or the ability to make one yourself. Also, don't place all of your chips on learning how to use iShit exploits. There are far more PC's than there are macs. kthxbai.