I'm working on some updates to to VF Fiddle. I want to gauge the interest in running fiddles in sandbox and get some feedback on the security concerns. Because fiddles are not reviewed they could potentially damage or leak information from a full-copy sandbox. They were originally intended for Developer Edition Orgs. However, I appreciate that many users do not have DE orgs.
Also, I will need some beta-testers as I don't have a sandbox login I can use, please let me know if you're willing to help.