'Covert' app lets jailbroken iPhones surf privately
Covert works as any other private browsing or history-cleaning software, eliminating history and cookies that might tell snoopers where the user had been. The great benefit of the app is that it integrates inconspicuously with the Mobile Safari interface.
To enable Covert, the user simply taps the 'Tabs' icon, and then selects 'Private Browsing'. They then begin a new off-the-record session, indicated by a dark gray hue of the user interface.
Covert is available for free from Cydia under the BigBoss repository. We won't tell.
source: Redmond Pie via Gizmodo