Okay, this is bloody amazing - a $2 app for jailbroken iPhones, tap your status bar and the camera is there in around half a second, without having to quit the current app. And there isn't a large memory hit to do this.

http://www.redmondpie.com/snappy-the-fastest-camera-app-for-jailbroken-iphone-9140131/
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If it's brokenless, don't suffix it...