I've just taken the plunge and ordered a windscreen mounted video camera. Based on this review, it seems the best for under £100.

REVIEW: Mini DVR 0801 The Smallest 1080p LCD Car Dash Cam with Ambarella A2S60 - Best Mini Car Cam - YouTube

How have others routed the power cable and have you used a permanent live or an ignition switched live ? The camera blurb says use a switched live supply so only comes on with ignition.

Can I tap into the positive supply in the interior light housing directly above the rear view mirror as I'd rather not have a lead all the way from the camera to the lighter socket?

I've got a A4 (B6) Cabriolet and would be interested to hear how others have powered their cameras.