NetShare
Nullriver has added a $9.99 utility to the app store called NetShare, which acts as a SOCKS5 proxy for your computer’s browser to view web pages. This isn’t quite tethering, which may explain why Apple allowed it to be released, but it is something.
Update – Apple pulled it down. Huge shock, I know.
Update 2 - It’s back up. Grab it while you can.