The HTC Flashilight app (flashlight.apk I believe) that was posted in an early thread here still works on my Vivid since the upgrade. The flashlight app was omitted from the Vivid, but someone found the apk file from an HD2 or other HTC phone. I installed it several months back, and it works well.
Edit: Here is where the apk is located. I had installed it under 2.3.4, and it still works with 4.0.3.
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