Accessing the web in Iran?

My father's out to Iran in a few days.

Any ideas on how to unblock the internet? (Not for Torrents or download as such, but mainly for proper Yahoo Mail access and access of his online Backups - though if it is for torrents, I could share the service for my usage).

I've read here and there that even VPN services have been blocked because of filtering out encrypted content.

So can anyone please help me out here?

Is there any VPN service somebody has personally tested out?