iPhone pin/password bypass vulnerability (to make calls and browse contacts and recent calls). It is similar to the iPhone pin bypass vulnerability found in October 2010 ( osvdb.org/show/osvdb/68928 vimeo.com/16179929 ).
This vulnerability is only verified on iOS 4.3.5.
An iOS 5 vulnerability to browse the camera rolls on a locked iPhone will be released later this year (maybe during Defcon).

Turn on the phone.
Slide to unlock.
Press Emergency Call.
Enter a very long phone number.
Press and hold down the Power button.
Wait for one second.
Press the Call button.
The phone will show the "Slide to power off" screen.
Release the Power button.
Press Cancel.
Double press the Home button.
Press the Phone icon.
Make calls.